Burden of disease of X-linked hypophosphatemia in Japanese and Korean patients: a cross-sectional survey.

The burden of disease of X-linked hypophosphatemia (XLH) in East Asia is poorly understood. This was a cross-sectional study using an online questionnaire to evaluate health-related quality of life (HRQOL) and disease complications in Japanese and Korean patients with XLH. Adults with XLH and the caregivers of children <18 years of age with XLH in Japan and Korea were surveyed. Respondents disclosed demographic data, family history, diagnostic history, medical history, surgical history, disease-specific clinical symptoms, treatment, medications, and use of ancillary equipment. Patient-reported outcomes (PROs; the Western Ontario and McMaster Universities Osteoarthritis Index, the brief pain inventory, and the 36-item short form health survey version 2) were used to assess pain, disability, and HRQOL in adults. Of those surveyed, all 14 children (100%) and 30/32 adults (93.8%) were receiving treatment for XLH. However, despite oral phosphate and active vitamin D use, short stature, gait abnormalities, dental conditions, and decreased physical function were reported. Stapling of the growth plates was reported in 14.3% of children but no adults. Adult patients reported high rates of bone pain (59.4%) and joint pain (65.6%). Caregivers of children with XLH also reported the occurrence of bone pain (35.7%) and joint pain (35.7%). Many adult patients had a history of impaired renal function (9.5%), nephrocalcinosis (15.6%), hyperparathyroidism (15.6%), and parathyroidectomy (6.3%), all of which are associated with conventional XLH treatments. These data show that patients (both pediatric and adult) continue to have symptoms such as pain, disability, and various complications despite receiving conventional therapies.

Comparative effect of dipeptidyl-peptidase 4 inhibitors on laboratory parameters in patients with diabetes mellitus.

BACKGROUND: The purpose of this study was to evaluate and compare the effects on laboratory parameters among monotherapy with five DPP-4 inhibitors in patients with type 2 diabetes mellitus (DM). METHODS: We identified cohorts of new sitagliptin users (n = 879), vildagliptin users (n = 253), teneligliptin users (n = 260), alogliptin users (n = 237), and linagliptin users (n = 180) in patients with type 2 DM. We used a multivariate regression model to evaluate and compare the effects of the drugs on laboratory parameters including HbA1c concentration and serum concentrations of creatinine, estimated glomerular filtration rate, high density lipoprotein, total cholesterol, triglyceride, aspartate aminotransferase, and alanine aminotransferase among the five DPP-4 inhibitors up to 12 months. RESULTS: Our study showed a favorable effect on HbA1c concentration and a slightly unfavorable effect on serum creatinine concentration in users of the five DPP-4 inhibitors, a favorable effect on lipid metabolism in sitagliptin, vildagliptin, and alogliptin users, and a favorable effect on hepatic parameters in sitagliptin, alogliptin, and linagliptin users, in comparison of the baseline and exposure periods. However, there was no significant difference in mean change in the concentration of any laboratory parameter among the five groups of DPP-4 inhibitor users. CONCLUSIONS: In this study, we showed the effect of five DPP-4 inhibitors on glycemic, renal, and lipid metabolism, and hepatic parameters. DPP-4 inhibitors are well-tolerated hypoglycemic drugs.

Association between use of oral hypoglycemic agents in Japanese patients with type 2 diabetes mellitus and risk of depression: A retrospective cohort study.

Type 2 diabetes mellitus (T2DM) is a risk factor for depression. Since brain insulin resistance plays a potential role in depression, the future risk of depression in patients with T2DM may be altered depending on the class of oral hypoglycemic agent (OHA) used for T2DM therapy. The aim of the present study was to determine if specific classes of OHAs are associated with a risk for comorbid depression in T2DM. Japanese adult patients with T2DM (n = 40 214) were divided into a case group (with depression; n = 1979) and control group (without depression; n = 38 235). After adjustment for age [adjusted odds ratio (AOR) for 10 years: 1.03; 95% confidence interval (CI): 0.99-1.07; P = .1211], sex [AOR for female: 1.39; 95% CI: 1.26-1.53; P < .0001], hemoglobin A1c [AOR for 1.0%: 1.18; 95% CI: 1.11-1.26; P < .0001], duration of T2DM [AOR for 1 year: 1.00; 95% CI: 0.99-1.01; P = .4089], and history of seven medical conditions, the odds ratios for the development of depression was significantly lower for dipeptidyl peptidase-4 (DPP-4) inhibitors [AOR: 0.31; 95% CI: 0.24-0.42; P < .0001]. However, there was no significant association for the other classes of OHAs. Therefore, this study finds that there is less risk of depression associated with the use of DPP-4 inhibitors for the treatment of T2DM.

Assessment of effect modification of statins on new-onset diabetes based on various medical backgrounds: a retrospective cohort study.

BACKGROUND: The aim of this study was to investigate the association between statin use and new-onset diabetes in clinical settings and to assess its effect modification (heterogeneity) among patients with various medical histories and current medications. METHODS: In a total of 12,177 Japanese patients without diabetes, from December 2004 to November 2012, we identified 500 statin users and 500 matched non-users using propensity-score matching. Patients were followed until December 2017. We estimated the hazard ratios of new-onset diabetes associated with statin use. We also tested the heterogeneity of the treatment effect by evaluating subgroup interactions in subgroups according to sex, age, medical history, and current medication. RESULTS: New-onset diabetes had occurred in 71 patients (13.6%) with statin use and 43 patients (8.3%) with non-use at 5 years (hazard ratio, 1.66; 95% confidence interval [CI], 1.11 to 2.48; P = 0.0143), and in 78 patients (15.6%) with statin use and 48 patients (9.6%) with non-use at 10 years (hazard ratio, 1.61; 95% CI, 1.10 to 2.37; P = 0.0141). There were no significant treatment-by-subgroup interactions in all subgroups defined according to sex, age, medical history, and current medication. CONCLUSIONS: In patients with various clinical backgrounds, those who received statin therapy had a higher risk of new-onset diabetes at 5 and 10 years than those who did not receive it. Effect modification of statins on new-onset diabetes was not found in patient populations defined according to various comorbid diseases or concomitant drugs.

A comprehensive analysis of association of medical history with airflow limitation: a cross-sectional study.

BACKGROUND: Multiple comorbidity is common and increases the complexity of the presentation of patients with COPD. This study was a comprehensive analysis of the relationship between a medical history of 22 disease categories and the presence of airflow limitation (AL) without any history of asthma or bronchiectasis, compatible with COPD. METHODS: A total of 11,898 Japanese patients aged ≥40 years, who underwent spirometry tests, comprising patients with AL (n=2,309) or without AL (n=9,589), were evaluated. Generalized estimating equations were used to assess the relationship between the presence of AL and each disease. The model was adjusted for age, sex, body mass index (BMI) and pack-years of smoking. RESULTS: In multivariate analysis, female sex (odds ratio [OR]: 0.59; 95% confidence interval [CI]: 0.52-0.67), age (OR for 10-year age increase: 1.99; CI: 1.90-2.09), BMI (OR for 1 kg/m2 increase: 0.96; CI: 0.95-0.98) and smoking history (<15 vs 15-24, 25-49 and ≥50 pack-years; OR: 1.78, 2.6 and 3.69, respectively; CI: 1.46-2.17, 2.24-3.0 and 3.15-4.33, respectively) were significantly associated with the presence of AL. In addition, a history of tuberculosis (OR: 1.72; CI: 1.39-2.11), primary lung cancer (OR: 1.50; CI: 1.28-1.77), myocardial infarction (OR: 1.22; CI: 1.01-1.48), heart failure (OR: 1.53; CI: 1.29-1.81), arrhythmia (OR: 1.19; CI: 1.03-1.38) or heart valve disorder (OR: 1.33; CI: 1.14-1.56) was significantly associated with the presence of AL, after adjustment. CONCLUSION: This study suggests that a history of heart disease leading to abnormal cardiac function may be associated with AL and that the presence of certain types of heart disease provides a rationale to assess lung status and look for respiratory impairment, including COPD.

Comparative Effect of Calcium Channel Blockers on Glomerular Function in Hypertensive Patients with Diabetes Mellitus.

BACKGROUND: We conducted a retrospective cohort study to evaluate and compare the longitudinal effect of monotherapy with L-, L/T-, L/N-, and L/N/T-type calcium channel blockers (CCBs) on estimated glomerular filtration rate (eGFR), and to investigate the association of treatment duration with eGFR in diabetic patients with hypertension. METHODS: Using a clinical database, we identified new users of five CCBs, i.e. amlodipine (L-type, n = 693), nifedipine (L-type, n = 189), azelnidipine (L/T-type, n = 91), benidipine (L/N/T-type, n = 183), and cilnidipine (L/N-type, n = 61). We used a multivariable regression model to evaluate and compare the effects of these drugs on eGFR and serum creatinine, up to 12 months after initiation of study drug administration. RESULTS: There was no significant association between treatment duration and both eGFR and serum creatinine level with all CCB types. In addition, there was no significant difference in mean change in eGFR among the five CCBs, with any treatment duration. CONCLUSIONS: Our findings suggest that monotherapy with an L-, L/T-, L/N/T-, or L/N-type CCB may have little influence on renal function parameters and may be safely used in hypertensive patients with diabetes.

A Comparative Effectiveness Study of Renal Parameters Between Imidapril and Amlodipine in Patients with Hypertension: A Retrospective Cohort Study.

INTRODUCTION: Imidapril is an angiotensin converting enzyme inhibitor (ACEI) that is frequently used as an antihypertensive drug in Japan. Although ACEIs are known to have adverse effects of decreasing glomerular filtration rate (GFR) and causing hyperkalemia, there are very few clinical data on the long-term effect of imidapril on glomerular function. We conducted a retrospective cohort study using a clinical database to evaluate and compare the long-term effects of imidapril and amlodipine on renal parameters in Japanese hypertensive patients in routine clinical practice. METHODS: We identified cohorts of new users of imidapril (n = 57) and a propensity score-matched group with an equal number of new users of amlodipine (n = 57). We used a multivariable regression model to evaluate and compare the effects of the drugs on laboratory parameters including serum levels of creatinine, potassium, sodium, blood urea nitrogen, and estimated GFR (eGFR) between imidapril users and amlodipine users up to 12 months after the initiation of study drug administration. The mean exposure of imidapril and amlodipine was 226.2 and 235.2 days, respectively. RESULTS: We found a significant increase of serum creatinine and potassium levels and a decrease of eGFR in imidapril users from the baseline period to the exposure period. The reduction of eGFR and the increase of serum creatinine and potassium levels in imidapril users were significantly greater than those in amlodipine users. CONCLUSIONS: Our study showed that imidapril decreased eGFR and increases the serum levels of creatinine and potassium compared with amlodipine, at least during 1 year of administration.

Comparative effect of fixed-dose combination tablets of candesartan cilexetil/amlodipine versus olmesartan medoxomil/azelnidipine on laboratory parameters in patients with hypertension: a retrospective cohort study.

We conducted a retrospective cohort study to evaluate and compare the long-term effects of two single-pill fixed-dose combinations (FDCs), candesartan/amlodipine and olmesartan/azelnidipine, on laboratory parameters in patients in routine clinical practice. We identified an equal number of new users (n = 182) of a candesartan/amlodipine (8/5 mg/day) FDC tablet (CAN/AML users) and a propensity-score matched cohort (n = 182) receiving an olmesartan/azelnidipine (20/16 mg/day) FDC tablet (OLM/AZ users). Generalized estimating equations were used to estimate and compare the effects of the drugs on serum levels of creatinine, estimated glomerular filtration rate (eGFR), blood urea nitrogen (BUN), uric acid, sodium, potassium, aspartate aminotransferase, and alanine aminotransferase levels up to 12 months after the start of study drug administration. There was a significant increase of serum creatinine level and a significant decrease of eGFR from the baseline period to during the exposure period in both CAN/AML and OLM/AZ users, and a significant increase of BUN level in CAN/AML users. However, there were no significant differences in the mean changes of laboratory parameters between CAN/AML and OLM/AZ users. Our findings suggested that the effects of CAN/AML and OLM/AZ on laboratory parameters, including an unfavorable effect on renal function, were similar at least during 1 year of administration.

Phosphorylated Sp1 is the regulator of DNA-PKcs and DNA ligase IV transcription of daunorubicin-resistant leukemia cell lines.

Multidrug resistance (MDR) is a serious problem faced in the treatment of malignant tumors. In this study, we characterized the expression of non-homologous DNA end joining (NHEJ) components, a major DNA double strand break (DSB) repair mechanism in mammals, in K562 cell and its daunorubicin (DNR)-resistant subclone (K562/DNR). K562/DNR overexpressed major enzymes of NHEJ, DNA-PKcs and DNA ligase IV, and K562/DNR repaired DSB more rapidly than K562 after DNA damage by neocarzinostatin (MDR1-independent radiation-mimetic). Overexpressed DNA-PKcs and DNA ligase IV were also observed in DNR-resistant HL60 (HL60/DNR) cells as compared with parental HL60 cells. Expression level of DNA-PKcs mRNA paralleled its protein level, and the promoter activity of DNA-PKcs of K562/DNR was higher than that of K562, and the 5'-region between -49bp and the first exon was important for its activity. Because this region is GC-rich, we tried to suppress Sp1 family transcription factor using mithramycin A (MMA), a specific Sp1 family inhibitor, and siRNAs for Sp1 and Sp3. Both MMA and siRNAs suppressed DNA-PKcs expression. Higher serine-phosphorylated Sp1 but not total Sp1 of both K562/DNR and HL60/DNR was observed compared with their parental K562 and HL60 cells. DNA ligase IV expression of K562/DNR was also suppressed significantly with Sp1 family protein inhibition. EMSA and ChIP assay confirmed higher binding of Sp1 and Sp3 with DNA-PKcs 5'-promoter region of DNA-PKcs of K562/DNR than that of K562. Thus, the Sp1 family transcription factor affects important NHEJ component expressions in anti-cancer drug-resistant malignant cells, leading to the more aggressive MDR phenotype.

Comparative effect of angiotensin II type I receptor blockers on serum uric acid in hypertensive patients with type 2 diabetes mellitus: a retrospective observational study.

BACKGROUND: Angiotensin II type 1 receptor blockers (ARB) are a frequently used class of antihypertensive drug. The ARB losartan is known to decrease the serum uric acid (SUA) level. However, there are very few clinical data comparing the effects of other ARBs on SUA level under the conditions of clinical practice. This study evaluated and compared the long-term effects of monotherapy with five ARBs on SUA level in Japanese hypertensive patients with type 2 diabetes mellitus (DM). METHODS: We identified hypertensive patients with type 2 DM who had been treated with monotherapy with losartan (n = 214), valsartan (n = 266), telmisartan (n = 185), candesartan (n = 458), or olmesartan (n = 192), in whom laboratory data of SUA between November 1, 2004 and July 31, 2011 were available, from the Nihon University School of Medicine's Clinical Data Warehouse (NUSM's CDW). We used a propensity-score weighting method and a multivariate regression model to adjust for differences in the background among ARB users, and compared the SUA level. The mean exposure of losartan was 264.7 days, valsartan 245.3 days, telmisartan 235.9 days, candesartan 248.9 days, and olmesartan 234.5 days. RESULTS: In losartan users, mean SUA level was significantly decreased from baseline, while it was conversely increased in users of other ARBs; valsartan, telmisartan, candesartan, and olmesartan. The mean reduction of SUA level from baseline was significantly greater in losartan users compared with that in other ARB users. Comparison of ARBs other than losartan showed no significant difference in mean change in SUA level from baseline. CONCLUSIONS: Our study showed that losartan had the most beneficial effect on SUA level among five ARBs, and that there was no significant difference in the unfavorable effects on SUA level among four ARBs other than losartan, at least during one year. These findings provide evidence of an effect of ARBs on SUA level, and support the benefit of the use of losartan in hypertensive patients with type 2 DM.

Comparative effect of clopidogrel and aspirin versus aspirin alone on laboratory parameters: a retrospective, observational, cohort study.

BACKGROUND: Clopidogrel and aspirin are antiplatelet agents that are recommended to reduce the risk of recurrent stroke and other cardiovascular events. Combination therapy of clopidogrel and aspirin has been shown to increase the risk of hemorrhage, but the effects of the drugs on laboratory parameters have not been well studied in patients in routine clinical practice. Therefore, we evaluated and compared the effects of combination therapy with clopidogrel plus aspirin and aspirin monotherapy on laboratory parameters using a clinical database. METHODS: We used data from the Clinical Data Warehouse of Nihon University School of Medicine obtained between November 2004 and April 2011, to identify cohorts of new users (n = 159) of clopidogrel (75 mg/day) plus aspirin (100 mg/day) and new users (n = 834) of aspirin alone (100 mg/day). We used a multivariable regression model and regression adjustment with the propensity score to adjust for differences in baseline covariates between settings, and compare the mean changes in serum levels of creatinine, aspartate aminotransferase, alanine aminotransferase and hematological parameters, including hemoglobin level, hematocrit, and white blood cell (WBC), red blood cell and platelet counts up to two months after the start of study drug administration. RESULTS: After adjustment, the reduction of WBC count in clopidogrel plus aspirin users was significantly greater than that in aspirin alone users. All other tests showed no statistically significant difference in the mean change from baseline to during the exposure period between clopidogrel plus aspirin users and aspirin alone users. The combination of clopidogrel and aspirin increased the risk of gastrointestinal bleeding compared with aspirin alone, with a relative risk ranging from 2.06 (95% CI, 1.02 to 4.13; p = 0.043) for the multivariate model and 2.61 (95% CI, 1.18 to 5.80; p = 0.0184) for propensity adjustment. CONCLUSION: Our findings suggested that hematological adverse effects may be greater with combination therapy of clopidogrel plus aspirin than with aspirin monotherapy.

Comparative effect of clopidogrel plus aspirin and aspirin monotherapy on hematological parameters using propensity score matching.

BACKGROUND: Clopidogrel and aspirin are antiplatelet agents that are recommended to reduce the risk of recurrent stroke and other cardiovascular events. Dual antiplatelet therapy with clopidogrel and aspirin has been shown to increase the risk of hemorrhage, but the effects of the drugs on laboratory parameters have not been well studied in real-world clinical settings. Therefore, we evaluated and compared the effects of combination therapy with clopidogrel plus aspirin and aspirin monotherapy on laboratory parameters. METHODS: We used data from the Nihon University School of Medicine Clinical Data Warehouse obtained between November 2004 and May 2011 to identify cohorts of new users (n = 130) of clopidogrel (75 mg/day) plus aspirin (100 mg/day) and a propensity score matched sample of new users (n = 130) of aspirin alone (100 mg/day). We used a multivariate regression model to compare serum levels of creatinine, aspartate aminotransferase, and alanine aminotransferase, as well as hematological parameters including hemoglobin level, hematocrit, and white blood cell, red blood cell, and platelet counts up to 2 months after the start of administration of the study drugs. RESULTS: There were no significant differences for any characteristics and baseline laboratory parameters between users of clopidogrel plus aspirin and users of aspirin alone. Reductions in white blood cell and red blood cell counts, hemoglobin levels, and hematocrit in users of clopidogrel plus aspirin were significantly greater than those in users of aspirin alone. CONCLUSION: Our findings suggest that adverse hematological effects may be greater with combination clopidogrel plus aspirin therapy than with aspirin monotherapy.

Involvement of KRAS G12A mutation in the IL-2-independent growth of a human T-LGL leukemia cell line, PLT-2.

Cytokine-dependent cell lines have been used to analyze the cytokine-induced cellular signaling and the mechanism of oncogenesis. In the current study, we analyzed MOTN-1 and PLT-2 cell lines established from different stages of a T-cell large granular lymphocyte leukemia patient (Daibata et al. 2004). MOTN-1 is IL-2-dependent derived from the chronic phase, whereas IL-2-independent PLT-2 is from the aggressive and terminal stage. They shared considerable chromosome abnormalities and the pattern of T-cell receptor rearrangement, presuming that the cytokine independence of PLT-2 was due to the additive genetic abnormality. Besides IL-2, IL-15 supported MOTN-1 cell growth, because these receptors share beta- and gamma-subunits. IL-2 activated ERK, AKT and STAT pathway of MOTN-1. STAT3 pathway of PLT-2 was also activated by IL-2, suggesting intact IL-2 induces signal transduction of PLT-2. However, ERK1/2 but not AKT, was continuously activated in PLT-2, consistent with the increased Ras-activity of PLT-2. Sequence analysis revealed KRAS G12A mutation but not NRAS and HRAS mutation of PLT-2 but not MOTN-1. Another signaling molecule affecting Ras-signaling pathway, SHP2, which has been frequently mutated in juvenile myelomonocytic leukemia (JMML), did not show mutation. Moreover, MEK inhibitor, PD98059, as well as farnesylation inhibitor inhibited PLT-2 cell growth. Using NIH3T3 and MOTN-1, ERK activation, increased cell proliferation and survival by KRAS G12A were shown, suggesting the important role of KRAS G12A in IL-2-independent growth of PLT-2. Taken together, KRAS G12A is important for IL-2-independent growth of PLT-2 cells and suggests the possibility of involvement of KRAS mutation with disease progression.

Comparative effect of angiotensin II type I receptor blockers and calcium channel blockers on laboratory parameters in hypertensive patients with type 2 diabetes.

BACKGROUND: Both angiotensin II type I receptor blockers (ARBs) and calcium channel blockers (CCBs) are widely used antihypertensive drugs. Many clinical studies have demonstrated and compared the organ-protection effects and adverse events of these drugs. However, few large-scale studies have focused on the effect of these drugs as monotherapy on laboratory parameters. We evaluated and compared the effects of ARB and CCB monotherapy on clinical laboratory parameters in patients with concomitant hypertension and type 2 diabetes mellitus. METHODS: We used data from the Clinical Data Warehouse of Nihon University School of Medicine obtained between Nov 1, 2004 and July 31, 2011, to identify cohorts of new ARB users (n = 601) and propensity-score matched new CCB users (n = 601), with concomitant mild to moderate hypertension and type 2 diabetes mellitus. We used a multivariate-adjusted regression model to adjust for differences between ARB and CCB users, and compared laboratory parameters including serum levels of triglyceride (TG), total cholesterol (TC), non-fasting blood glucose, hemoglobin A1c (HbA1c), sodium, potassium, creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), hemoglobin and hematocrit, and white blood cell (WBC), red blood cell (RBC) and platelet (PLT) counts up to 12 months after the start of ARB or CCB monotherapy. RESULTS: We found a significant reduction of serum TC, HbA1c, hemoglobin and hematocrit and RBC count and a significant increase of serum potassium in ARB users, and a reduction of serum TC and hemoglobin in CCB users, from the baseline period to the exposure period. The reductions of RBC count, hemoglobin and hematocrit in ARB users were significantly greater than those in CCB users. The increase of serum potassium in ARB users was significantly greater than that in CCB users. CONCLUSIONS: Our study suggested that hematological adverse effects and electrolyte imbalance are greater with ARB monotherapy than with CCB monotherapy.

Comparison of the effect of mesalazine and sulfasalazine on laboratory parameters: a retrospective observational study.

PURPOSE: Mesalazine and sulfasalazine are commonly used drugs for the treatment of inflammatory bowel disease. However, there have been few reports with a strict statistical analysis comparing the effects of mesalazine and sulfasalazine on laboratory test results. Therefore, we designed a retrospective cohort study to investigate whether or not differences in clinical laboratory parameters exist between mesalazine and sulfasalazine users. METHODS: We used data from the Clinical Data Warehouse of Nihon University School of Medicine to identify cohorts of new mesalazine users (n = 303) and sulfasalazine users (n = 67). We used a multivariate regression model and regression adjustment with the propensity score to adjust for differences in baseline covariates between mesalazine and sulfasalazine users, and compared serum levels of creatinine, urea nitrogen, aspartate aminotransferase, alanine aminotransferase, and hematological parameters including red and white blood cell counts and platelet count. RESULTS: After adjustment, in sulfasalazine users, the mean values for all tests showed no significant change between baseline and during the exposure period. In contrast, in mesalazine users, the mean WBC and platelet counts during the exposure period were significantly lower than those at baseline. Furthermore, mean serum urea nitrogen level during the exposure period was significantly higher than that at baseline. In terms of mean changes in laboratory test values during the exposure period compared with baseline, the reduction of platelet count in mesalazine users was significant in comparison to that in sulfasalazine users. CONCLUSION: Our findings suggested that the hematological adverse effects of mesalazine treatment might be greater than those of sulfasalazine treatment.

Utilization of health care databases for pharmacoepidemiology.

Pharmacoepidemiology is the study of the utilization and effects of drugs in clinical and population settings, and the outcomes of drug therapy. The growing trend of recording computerized data that will increasingly be automated into health care delivery is making the use of large datasets more and more common in pharmacoepidemiologic research. Most retrospective databases offer large populations and longer observation periods with real-world practice and can answer a variety of research questions quickly and cost-effectively. Observational studies, specifically using large databases, can complement findings from randomized clinical trials (RCTs) by assessing treatment effectiveness in patients encountered in daily clinical practice, although they are more exposed to bias and certainly are lower on the hierarchy of evidence than RCTs. Furthermore, careful defining of the research question with appropriate design and application of advanced statistical techniques, e.g., propensity-score analysis or marginal structural models, can yield findings with validity and improve causal inference of treatment effects. Some existing guidelines for comparative effectiveness help decision makers to evaluate the quality of observational studies comparing the effectiveness of various medical products and services. Thus, the trend for utilization of databases for pharmacoepidemiology will continue to grow in coming years.

Comparative effect of olmesartan and candesartan on lipid metabolism and renal function in patients with hypertension: a retrospective observational study.

BACKGROUND: Angiotensin II receptor blockers (ARBs), including olmesartan and candesartan, are widely used antihypertensive agents. Many clinical studies have demonstrated that ARBs have organ-protecting effects, e.g., cardioprotection, vasculoprotection and renoprotection. However, the effect of prolonged olmesartan monotherapy on lipid metabolism in patients with hypertension is less well studied. We performed a retrospective observational study to compare the effects of olmesartan with those of candesartan, focusing on lipid metabolism and renal function. METHODS: We used data from the Clinical Data Warehouse of Nihon University School of Medicine obtained between Nov 1, 2004 and Feb 28, 2011, to identify cohorts of new olmesartan users (n = 168) and candesartan users (n = 266). We used propensity-score weighting to adjust for differences in all covariates (age, sex, comorbid diseases, previous drugs) between olmesartan and candesartan users, and compared serum chemical data including serum triglyceride (TG), LDL-cholesterol (LDL-C), total cholesterol (TC), potassium, creatinine and urea nitrogen. The mean exposure of olmesartan and candesartan users was 126.1 and 122.8 days, respectively. RESULTS: After adjustment, there were no statistically significant differences in all covariates between olmesartan and candesartan users. The mean age was 60.7 and 61.0 years, and 33.4% and 33.7% of olmesartan and candesartan users were women, respectively. There were no statistically significant differences in mean values for all laboratory tests between baseline and during the exposure period in both olmesartan and candesartan users. In olmesartan users, the reduction of serum TG level was significant in comparison with that in candesartan users. Other parameters of lipid profile and renal function showed no statistically significant difference in the change from baseline to during the exposure period between olmesartan and candesartan users. CONCLUSIONS: In this study, we observed a more beneficial effect on lipid metabolism, a reduction of serum TG, with olmesartan monotherapy than with candesartan monotherapy. However, there were no clinically significant changes in the levels of all test parameters between baseline and during the exposure period with both drugs. These results suggest that the influence of olmesartan or candesartan monotherapy on lipid metabolism and renal function is small, and that they can be safely used in patients with hypertension.

Adverse effect profile of trichlormethiazide: a retrospective observational study.

BACKGROUND: Trichlormethiazide, a thiazide diuretic, was introduced in 1960 and remains one of the most frequently used diuretics for treating hypertension in Japan. While numerous clinical trials have indicated important side effects of thiazides, e.g., adverse effects on electrolytes and uric acid, very few data exist on serum electrolyte levels in patients with trichlormethiazide treatment. We performed a retrospective cohort study to assess the adverse effects of trichlormethiazide, focusing on serum electrolyte and uric acid levels. METHODS: We used data from the Clinical Data Warehouse of Nihon University School of Medicine obtained between Nov 1, 2004 and July 31, 2010, to identify cohorts of new trichlormethiazide users (n = 99 for 1 mg, n = 61 for 2 mg daily dosage) and an equal number of non-users (control). We used propensity-score matching to adjust for differences between users and control for each dosage, and compared serum chemical data including serum sodium, potassium, uric acid, creatinine and urea nitrogen. The mean exposure of trichlormethiazide of 1 mg and 2 mg users was 58 days and 64 days, respectively. RESULTS: The mean age was 66 years, and 55% of trichlormethiazide users of the 1 mg dose were female. In trichlormethiazide users of the 2 mg dose, the mean age was 68 years, and 43% of users were female. There were no statistically significant differences in all covariates (age, sex, comorbid diseases, past drugs, and current antihypertensive drugs) between trichlormethiazide users and controls for both doses. In trichlormethiazide users of the 2 mg dose, the reduction of serum potassium level and the elevation of serum uric acid level were significant compared with control, whereas changes of mean serum sodium, creatinine and urea nitrogen levels were not significant. In trichlormethiazide users of the 1 mg dose, all tests showed no statistically significant change from baseline to during the exposure period in comparison with control. CONCLUSIONS: Our study showed adverse effects of decreased serum potassium and increased serum uric acid with trichlormethiazide treatment, and suggested that a lower dose of trichlormethiazide may minimize these adverse effects. These findings support the current trend in hypertension therapeutics to shift towards lower doses of thiazides.

Effect of candesartan monotherapy on lipid metabolism in patients with hypertension: a retrospective longitudinal survey using data from electronic medical records.

BACKGROUND: Studies focusing on the add-on effects of angiotensin II type 1 receptor blockers (ARBs) other than their antihypertensive effect are receiving attention. However, the effects of prolonged administration of ARBs on lipid metabolism in clinical cases are unclear. Our aims were to survey the changes in plasma lipid profile in patients with hypertension over a one-year period, and to examine the correlations between these values and the time after the start of ARB monotherapy with candesartan. METHODS: We carried out candesartan monotherapy in patients with mild to moderate hypertension and examined the longitudinal changes in plasma lipid profile. Data from 405 patients for triglyceride (TG), 440 for total cholesterol (TC), 313 for high density lipoprotein cholesterol (HDL-C) and 304 for low density lipoprotein cholesterol (LDL-C) were obtained from the electronic medical records (EMRs) in the Clinical Data Warehouse (CDW) of Nihon University School of Medicine (NUSM). The inverse probability of treatment weighting (IPTW) method (calculated from the inverse of the propensity score) was used to balance the covariates and reduce bias in each treatment duration. Linear mixed effects models were used to analyse the relationship between these longitudinal data of blood examinations and covariates of patient sex, age, diagnosis of diabetes mellitus (DM) and duration of candesartan monotherapy. RESULTS: Plasma HDL-C level was associated with sex, duration of treatment, and interaction of sex and treatment duration, but not with age or diagnosis of DM. HDL-C level was significantly decreased during the 6 approximately 9 months period (p = 0.0218) compared with baseline. TG and TC levels were associated with sex, but not with age, diagnosis of DM or treatment duration. LDL-C level was not associated with any covariate. Analysis of the subjects divided by sex revealed a decrease in HDL-C in female subjects (during the 6 approximately 9 months period: p = 0.0054), but not in male subjects. CONCLUSIONS: Our study revealed that administration of candesartan slightly decreased HDL-C in female subjects. However, TG, TC and LDL-C levels were not influenced by candesartan monotherapy. Candesartan may be safely used for patients with hypertension with respect to lipid metabolism, because the effect of candesartan on lipids may be small.

Global profiling of influence of intra-ischemic brain temperature on gene expression in rat brain.

Mild to moderate differences in brain temperature are known to greatly affect the outcome of cerebral ischemia. The impact of brain temperature on ischemic disorders has been mainly evaluated through pathological analysis. However, no comprehensive analyses have been conducted at the gene expression level. Using a high-density oligonucleotide microarray, we screened 24000 genes in the hippocampus under hypothermic (32 degrees C), normothermic (37 degrees C), and hyperthermic (39 degrees C) conditions in a rat ischemia-reperfusion model. When the ischemic group at each intra-ischemic brain temperature was compared to a sham-operated control group, genes whose expression levels changed more than three-fold with statistical significance could be detected. In our screening condition, thirty-three genes (some of them novel) were obtained after screening, and extensive functional surveys and literature reviews were subsequently performed. In the hypothermic condition, many neuroprotective factor genes were obtained, whereas cell death- and cell damage-associated genes were detected as the brain temperature increased. At all intra-ischemic brain temperatures, multiple molecular chaperone genes were obtained. The finding that intra-ischemic brain temperature affects the expression level of many genes related to neuroprotection or neurotoxicity coincides with the different pathological outcomes at different brain temperatures, demonstrating the utility of the genetic approach.