Association of aortic valve calcification with carotid artery lesions and peripheral artery disease in patients with chronic kidney disease: a cross-sectional study.

BACKGROUND: Patients with chronic kidney disease (CKD) reportedly have a high prevalence of aortic valve calcification (AVC). In population-based studies, AVC is considered a manifestation of systemic atherosclerosis. The association of AVC with atherosclerotic lesions has not been fully investigated in predialysis patients. The present study was performed to determine whether carotid artery lesions and peripheral artery disease (PAD) are associated with AVC in patients with CKD not on dialysis. METHODS: In total, 749 patients were included in this cross-sectional study. AVC was evaluated using echocardiography. Carotid artery lesions including carotid artery plaque (CAP) and PAD were simultaneously examined in each patient. A logistic regression analysis was applied to determine the factors associated with AVC. RESULTS: AVC, CAP, and PAD were found in 201, 583, and 123 patients, respectively. In the multivariable analyses adjusted for covariates including the estimated glomerular filtration rate and makers of mineral metabolism (serum calcium, serum phosphorus, parathyroid hormone, 1,25-dihydroxyvitamin D, and fibroblast growth factor 23), AVC was significantly associated with the presence of CAP [odds ratio (OR), 3.37; 95% confidence interval (CI), 1.43-7.95], the presence of PAD (OR, 1.76; 95% CI, 1.10-2.81), the CAP score (per 1.0-point increase) (OR, 1.06; 95% CI, 1.02-1.11), and the ankle-brachial blood pressure index (per 0.1-point increase) (OR, 0.83; 95% CI, 0.72-0.95). CONCLUSIONS: AVC was associated with atherosclerotic lesions independent of kidney function and mineral metabolism. We consider that this association between AVC and atherosclerosis might reflect the burden of shared atherosclerotic risk factors.

Antihypertensive drug reduction for treated hypertensive patients during the summer.

Seasonal winter-summer variation in blood pressure (BP) has been reported, but there are few reports on the reduction of antihypertensive medication during the summer. We aimed to investigate the prevalence and details of drug reduction during the summer among outpatients. Among 667 patients, 90 patients (13.5%) had their medication reduced during the summer. The highest rate of drug reduction was for diuretics (17.5%). The patients whose medications were reduced (Group R) took a larger number of drugs and more frequently took diuretics compared with the subjects whose medications were unchanged (N = 559; with no reduction or increase in drugs, Group UC). Moreover, both the office BP and morning home BP of the patients in Group R were significantly lower compared with those of the patients in Group UC. These results suggest that doctors tend to reduce antihypertensive drugs to avoid an excessive decrease in BP especially in patients receiving combination therapy including diuretics.

Comparison of Prognostic Values of Daytime and Night-Time Systolic Blood Pressures on Renal Outcomes in Patients With Chronic Kidney Disease.

BACKGROUND: Differences in the predictive value of daytime systolic blood pressure (SBP) and night-time SBP by ambulatory blood pressure monitoring on renal outcomes have not been fully investigated in chronic kidney disease (CKD) patients. This study compared the prognostic value between daytime and night-time SBP on renal outcomes in CKD.Methods and Results:This prospective observational study included 421 patients. The composite renal endpoint was endstage renal disease (ESRD) or death. Cox models were used to determine associations of daytime and night-time SBP with renal outcomes. There were 150 renal events (ESRD, 130; death, 20). Multivariable Cox analyses demonstrated that hazard ratios (HRs) [95% confidence interval (CI)] for composite renal outcomes of every 10-mmHg increase in daytime and night-time SBP levels were 1.13 (1.02-1.26) (P=0.02) and 1.15 (1.05-1.27) (P<0.01), respectively. In addition, compared with the 1st daytime or night-time SBP quartile, HRs (95% CI) for outcomes in the 2nd, 3rd, and 4th quartiles were: daytime SBP, 1.25 (0.70-2.25), 1.09 (0.61-1.94), and 1.58 (0.88-2.85; P=0.13) (P for trend=0.16); night-time SBP, 1.09 (0.61-1.96), 1.31 (0.76-2.28), and 1.82 (1.00-3.30; P=0.049) (P for trend=0.03), respectively. CONCLUSIONS: Night-time SBP appeared superior to daytime SBP for predicting renal outcomes in this population of patients.

Salt Intake, Home Blood Pressure, and Perinatal Outcome in Pregnant Women.

BACKGROUND: The relationship between salt (sodium chloride) intake and pregnancy-induced hypertension (PIH) remains unclear. The aim of this study was therefore to investigate the current status of salt intake during pregnancy and identify effective predictors for PIH. METHODS AND RESULTS: Participants were 184 pregnant women who collected 24-h home urine as well as early morning urine samples. We investigated urinary salt excretion, home blood pressure (HBP) measurements for 7 consecutive days before the 20th and after the 30th gestational week, and the development of PIH. Urinary salt excretion according to early morning urine before the 20th gestational week was 8.6±1.7 g/day, and was significantly correlated with that measured from 24-h collected urine. Early morning urine estimated urinary salt excretion was slightly but significantly increased during pregnancy. HBP was 102±10/63±8 mmHg before the 20th gestational week and 104±12/64±10 mmHg after the 30th gestational week. On multiple regression analysis, serum uric acid and body mass index, but not urinary salt excretion, contributed to HBP both before the 20th and after the 30th gestational week. Fourteen participants (7.6%) developed PIH. On multivariate analysis, higher HBP and older age, but not urinary salt excretion, were significantly associated with PIH. CONCLUSIONS: Higher HBP and older age, but not urinary salt excretion, are predictors of PIH. (Circ J 2016; 80: 2165-2172).

Variability of urinary salt excretion estimated by spot urine in treated hypertensive patients.

Among the several methods used to assess salt intake, estimating 24 h urinary salt excretion by spot urine seems appropriate for clinical practice. In this study, we investigated variability in urinary salt excretion using spot urine in hypertensive outpatients. Participants included 200 hypertensive patients who underwent spot urinary salt excretion at least three times during the observation period. Mean urinary salt excretion and the coefficient of the variation were 8.62 ± 1.96 g/day and 19.0 ± 10.2%, respectively. In the analysis of participants who underwent assessment of urinary salt excretion at least eight times (n = 54), a significant reduction in mean urinary salt excretion was found at the 5th measurement. On the contrary, the coefficient of the variation of urinary salt excretion continued to increase until the 5th measurement, and became stable thereafter. Mean urinary salt excretion was positively correlated with mean clinic diastolic blood pressure (r = 0.27, p < 0.05). Clinic diastolic blood pressure in the high urinary salt excretion group (≥ 10 g/day) was significantly higher than that of the low group (76.2 ± 7.5 vs 73.4 ± 8.3 mmHg, p < 0.05). Mean urinary salt excretion in summer was significantly lower than that of the other seasons (7.75 ± 1.94 vs 9.09 ± 2.68 (spring), 8.72 ± 2.12 (autumn), 8.92 ± 2.17 (winter) g/day, p < 0.01). In conclusion, repeated measurements of urinary salt excretion using spot urine are required to assess daily salt intake of hypertensive patients.

Effect of losartan on serum uric acid in hypertension treated with a diuretic: the COMFORT study.

It has been shown that losartan, an angiotensin II receptor blocker (ARB), reduces serum uric acid levels. However, the effects of losartan on serum uric acid levels in the patients treated with a thiazide diuretic have not been fully elucidated. We have investigated the effects of losartan compared with other ARBs on blood variables and blood pressure control in hypertensive patients treated with a thiazide diuretic using data from the COMFORT study. The present analysis included a total of 118 hypertensive subjects on combination treatment with ARBs except for losartan and a diuretic who were randomly assigned to a daily regimen of a combination pill (losartan 50 mg/hydrochlorothiazide 12.5 mg) or to continuation of two pills, an ARB except for losartan and a diuretic. Blood pressures were evaluated at 1, 3, and 6 months after randomization and changes in blood variables including serum uric acid were evaluated during 6 months treatment period. Mean follow-up blood pressure levels were not different between the combination pill (losartan treatment) group and the control (ARBs except for losartan) group. On the other hand, serum uric acid significantly decreased in the combination pill group compared with the control group (-0.44 versus + 0.10 mg/dl; p = 0.01), although hematocrit, serum creatinine, sodium and potassium were not different between the groups. These results suggest that the treatment regimen switched from a combination therapy of ARBs except for losartan and a diuretic to a combination pill (losartan/ hydrochlorothiazide) decreases serum uric acid without affecting blood pressure control.

Overcoming Clinical Inertia in the Treatment of Hypertension.

Objective This study aimed to investigate the antihypertensive goal achievement rate for office blood pressure (OBP) and the rate of clinical inertia (inertia) as factors for non-achievement in hypertensive patients in 2020. After documenting these results in the medical records, we observed changes in the achievement rate of the OBP goals in 2020 and 2022. Methods In Study 1, the participants were 517 outpatients (mean age 68.6±13.2 years, 54% women) who visited the Division of Hypertension regularly between March and September 2020. We investigated the achievement rate of OBP goals during that period and confirmed the prevalence of inertia as a possible factor for failure to achieve OBP goals. In Study 2, the participants were 308 who visited the division, and who had at least one condition for which an OBP of <130/80 should be targeted in both 2020 and 2022 (mean age 66.6±12.4 years, 50% of women in 2020). We investigated the trends in the achievement of OBP for the same period in both years. Results The rate of achievement of the OBP goals in 2020 was 48%. Inertia accounted for 14% of the non-achievement factors. The OBP significantly decreased in 2022 in comparison to 2020. The achievement rate of OBP goals showed an increasing trend from 45% in 2020 to 52% in 2022. Conclusion Attending physicians' awareness of unmet antihypertensive goals can help them overcome inertia and improve blood pressure control in patients.

Association of systolic blood pressure and pulse pressure with carotid intima thickness in elderly Japanese patients.

Many studies have demonstrated that increased carotid intima-media thickness (IMT) is related to future cardiovascular events and is influenced by cardiovascular risk factors such as sex, hypertension, diabetes, and hypercholesterolemia. Although aging is a well-known risk factor for an increase in carotid IMT, few studies have investigated which factors influence carotid IMT in the very elderly. In the present study, we investigated the relationship of pulse pressure (PP), blood pressure (BP), and its variability (six consecutive visits) with carotid IMT among 240 high-risk elderly in whom risk factors were managed clinically (average age was 79 ± 5 years). In the simple correlation, mean systolic BP (SBP) had a positive correlation with IMT and max IMT (P = .012 and P = .045), as did PP (P = .018 and P = .004), but did not diastolic BP or standard deviation of BP and coefficient of variation of BP. In multiple regression analyses, mean SBP and mean PP were each determinants of both IMT and max IMT, when each parameter was added separately to the regression model. We concluded that high SBP and wide PP still have an influence on increased carotid IMT in the very elderly Japanese patients.

Does a combination pill of antihypertensive drugs improve medication adherence in Japanese? A randomized controlled trial.

BACKGROUND: In order to achieve target blood pressure levels to prevent cardiovascular disease, combination therapy of antihypertensive drugs is often required, although it is thought that requiring a patient to take many different pills would reduce adherence to the medication regimen. Whether antihypertensive treatment with a single pill combining antihypertensive drugs would improve medication adherence and blood pressure control was investigated. METHODS AND RESULTS: A total of 207 hypertensive subjects were randomly assigned to a combination pill group (losartan 50mg/hydrochlorothiazide 12.5mg; n=103) or a control group (an angiotensin receptor blocker and a thiazide diuretic; n=104). Medication adherence was evaluated by pill counts at 1, 3, and 6 months after randomization. The mean adherence rates over 6 months were not different between the 2 groups: 98% in the combination pill group and 98% in the control group. Moreover, the 2 groups included similar numbers of subjects with relatively poor adherence rates (<90%) in each treatment period. The mean blood pressures over the 6-month treatment period were not different between the groups: 131/75 mmHg in the combination pill group and 130/75 mmHg in the control group (P=0.84/0.96). CONCLUSIONS: There were no appreciable effects of the combination pill of antihypertensive drugs on medication adherence or blood pressure control in Japanese patients over a 6-month period.

Antiproteinuric effect of cilnidipine in hypertensive Japanese treated with renin-angiotensin-system inhibitors - a multicenter, open, randomized trial using 24-hour urine collection.

Sustained proteinuria is an important risk factor for not only renal but also cardiovascular morbidity and mortality. Although inhibitors of the renin-angiotensin system (RAS) have been shown to reduce proteinuria. Monotherapy with those drugs is often insufficient for optimal blood pressure (BP)-lowering and therefore, combined therapy is needed. Recent reports suggested that cilnidipine, a dual L-/N-type calcium channel blocker, has renoprotective effect by dilating both efferent and afferent arterioles. In this study, a multicenter, open, randomized trial was designed to compare the antiproteinuric effect between cilnidipine and amlodipine when coupled with RAS inhibitors in hypertensive patients with significant proteinuria. Proteinuria was evaluated by 24-h home urine collection for all patients. A total of 35 proteinuric (>0.1 g/day) patients with uncontrolled BP (>135/85 mmHg) were randomized to receive either cilnidipine (n = 18) or amlodipine (n = 17) after a 6-month treatment with RAS inhibitors and were followed for 48 weeks. At baseline, the cilnidipine group was older and had lower body mass index (BMI) compared to the amlodipine group. After 32 weeks of treatment, diastolic blood pressure (DBP) was slightly, but significantly reduced, in the cilnidipine group, although systolic blood pressure (SBP) and mean BP did not differ. The urinary protein did not differ at baseline (cilnidipine group 0.48 g/day, amlodipine group 0.52 g/day); however, it significantly decreased in the cilnidipine group (0.22 g/day) compared to the amlodipine group (0.50 g/day) after 48 weeks of treatment. Our findings suggest that cilnidipine is superior to amlodipine in preventing the progression of proteinuria in hypertensive patients even undergoing treatment with RAS inhibitors.

Current prescription status of antihypertensive drugs with special reference to the use of diuretics in Japan.

The guidelines for the management of hypertension recommend the inclusion of diuretics, especially when three or more antihypertensive drugs are used. The present study investigated the current prescription status of antihypertensive drugs with a particular focus on the use of diuretics in a local district in Japan. Prescriptions, including antihypertensive drugs, were collected from a dispensing pharmacy of the Yahata Pharmacist Association, located in Kitakyushu City, in October 2014. Of the 10 585 prescriptions, calcium channel blockers (CCBs) were prescribed in 73.5%, followed by angiotensin II receptor blockers (ARB, 62.7%), diuretics (16.5%) and ß-blockers (13.6%). The average number of drugs used was 1.80. The rates of prescription of diuretics for patients with one, two, three and four drugs were 0.6%, 13.1%, 55.2% and 82.6%, respectively. Diuretics were more frequently prescribed in elderly patients, and the prescription rate of doctors in hospitals was significantly higher than that of general practitioners (19.1% vs. 15.7%, P<0.01). In addition, 40% of patients with thiazide diuretics were prescribed combination tablets of hydrochlorothiazide with ARB, whereas trichlormethiazide (34.9%) and indapamide (19.8%) were used in other patients. Based on these findings, the use of diuretics remains limited, even among patients taking multiple antihypertensive drugs.

Orthostatic Hypotension Predicts a Poor Prognosis in Elderly People with Dementia.

Objective The purpose of the present study was to assess the prevalence of orthostatic hypotension (OH) and elucidate its associations with the demographic characteristics and the prognosis in elderly subjects with dementia who visited a hospital for elderly daycare. Methods A total of 64 outpatients (44 females) with a mean age of 84±6 years who visited a hospital for daycare were enrolled in the study. The prevalence of OH and demographic characteristics were examined. Then, the subjects were followed up for 1 year. The blood pressure was measured in the supine position and immediately, 1, 3 and 5 minutes after standing. Poor outcome measures included death, hospitalization for any reason, and admission to a nursing home or geriatric facility. Results OH was present in 17 patients (26.6%). The presence of OH was associated with a higher supine systolic blood pressure. The increase in heart rate in the standing position was also reduced in subjects with OH compared with those without. The presence of OH was associated with faster time in the timed up-and-go test compared with those without OH. During the follow-up period, 22 patients (34.4%) had a poor prognosis, of which 8 (36.4%) had OH, which tended to be higher than those with a favorable prognosis. The event-free survival rate appeared to be lower in subjects with OH than in those without. Conclusion OH is relatively common in frail elderly patients with dementia, and it also appears to be associated with a poor prognosis.

Plasma B-type natriuretic peptide concentration is independently associated with kidney function decline in Japanese patients with chronic kidney disease.

BACKGROUND AND OBJECTIVE: The relationship between B-type natriuretic peptide (BNP) concentration and renal outcomes in patients with chronic kidney disease (CKD) remains unclear; therefore, it has not been determined whether BNP is related to renal outcomes, independent of cardiac parameters. This study was designed to clarify whether BNP concentration is associated with renal outcomes in CKD patients, independent of cardiac functional and structural alterations. METHODS: This prospective observational study included 372 consecutive patients with CKD. The renal endpoint was the composite of doubling of serum creatinine concentration and end-stage renal disease requiring dialysis. BNP concentrations were divided into quartiles. A Cox proportional hazards model was utilized to determine the risk factors for poor renal outcomes. RESULTS: During a median follow-up of 23.1 months, the renal endpoint was observed in 124 patients, including 14, 18, 37 and 55 patients in the first through fourth BNP quartiles, respectively. After adjustment for covariates, including cardiac parameters such as left atrial diameter, left ventricular mass index, left ventricular ejection fraction, and left ventricular hypertrophy, the hazard ratios (HRs) for renal outcomes became progressively higher for the second [HR, 1.50; 95% confidence interval (CI), 0.70-3.30), third (HR, 2.29; 95% CI, 1.11-4.91), and fourth (HR, 4.29; 95% CI, 2.05-9.39) BNP quartiles when compared with the lowest BNP quartile. CONCLUSION: Higher BNP levels were associated with adverse renal outcomes, independent of cardiac structure and function, suggesting that BNP may be a useful biomarker for exploring factors associated with kidney disease progression.

A Cushing's syndrome patient's severe insomnia and morning blood pressure surge both improved after her left adrenal tumor resection.

Underlying mechanisms of the elevated risks of hypertension and cardiovascular disease (CVD) in Cushing's syndrome (CS) are unclear. We treated an adult woman with CS because of a cortisol-secreting adrenal tumor. After tumor resection, the 24-h blood pressure (BP) level improved from 156/91 to 131/84 mmHg; the morning BP surprisingly improved from 174/98 to 127/93 mmHg, although we reduced her antihypertensive medication. Her sleep quality (by the Pittsburgh Sleep Quality Index) improved from 7 to 2 points. Disturbed circadian BP rhythm is often observed in CS, but was reported only as altered nocturnal BP fall. This is the first report showing the disappearance of the morning BP surge evaluated by ambulatory BP monitoring with postsurgery sleep quality improvement. Poor-quality sleep, followed by exaggerated morning BP surge may thus be a cause of CS-related cardiovascular events. Sleep quality and BP circadian rhythm evaluations may clarify hypertension and high CVD risk in CS.

Long-term compliance with salt restriction in Japanese hypertensive patients.

The purpose of the present study was to investigate the long-term compliance with salt restriction in Japanese hypertensive patients. Subjects included 389 patients, 230 women and 159 men, mean age 58+/-11 years, who underwent successful 24-h home urine collection more than three times over an interval of a year. Urinary salt, potassium, and creatinine were measured. Additionally, family history, habitual alcohol intake, smoking habit, physical activities, and job status were assessed by use of a questionnaire. During the follow-up period (average 3.5 years), participants underwent urine collection 4.6 times in average. Urinary salt excretion at the last visit was significantly lower than that at the first visit (8.7+/-3.4 vs. 9.6+/-4.1 g/day; p<0.01). Urinary potassium excretion also decreased significantly during this period (from 2.0+/-0.7 to 1.9+/-0.7 g/day; p<0.05). Among the mean 4.6 urine collections, 45.2% (men 34.6%, women 52.6%) of the patients successfully achieved <6 g (100 mmol of sodium)/day of salt excretion on at least one occasion. The rate of achievement of averaged urinary salt excretion <6 g/day dropped to 10.3% (men 4.4%, women 14.3%). Only 2.3% (men 0.6%, women 3.5%) of the patients achieved <6 g/day on all occasions. There were no significant differences in age, habitual alcohol intake, smoking habit, physical activities, or job status between patients who complied with the salt-restricted diet and those who did not. Results suggest that long-term compliance with salt restriction is poor in Japanese hypertensive patients. Since no specifically defining characteristics were found in the compliant patients, repeated measurements of urinary salt excretion seem to be important to encourage salt restriction.

Relationship between salt intake as estimated by a brief self-administered diet-history questionnaire (BDHQ) and 24-h urinary salt excretion in hypertensive patients.

Assessing an individual's salt intake is necessary for providing guidance with respect to salt restriction. However, the methods that exist for assessing salt intake have both merits and limitations. Therefore, the evaluation methods should be selected for their appropriateness to the patients and the environment of the medical facilities. The purpose of the present study was to investigate the validity of a brief self-administered diet-history questionnaire (BDHQ) by comparing the responses with 24-h urinary salt excretion. A total of 136 hypertensive outpatients (54 men and 82 women) were included in this study. All subjects were given the BDHQ and performed 24-h home urine collection. The energy-adjusted salt intake as assessed by the BDHQ was 12.3 (95% confidence interval: 11.8-12.9) g per day, and the urinary salt excretion evaluated by 24-h urinary collection was 9.0 (8.4-9.5) g per day. The energy-adjusted salt intake assessed by the BDHQ correlated significantly with the urinary salt excretion evaluated by 24-h urinary collection (r=0.34, P<0.001). In conclusion, the estimated salt intake evaluated by the BDHQ weakly, but significantly, correlated with 24-h urinary salt excretion. In clinical practice, it seems important to utilize both methods to assess an individual's salt intake in order to provide adequate guidance for salt restriction.

Relationship between the awareness of salt restriction and the actual salt intake in hypertensive patients.

A 24-h home urine collection was conducted to estimate accurate salt intake in hypertensive outpatients. Using 24-h urinary creatinine excretion as a criterion for success, urine samples were obtained from 534 hypertensive patients. The urinary salt excretion of hypertensive outpatients ranged widely from 1.5 to 23.4 g/day (mean value 9.7 +/- 3.9 g/day). Urinary salt excretion was higher in males than in females (10.6 +/- 4.0 vs. 9.2 +/- 3.7 g/day, p<0.01). Based on the questionnaires, the patients were divided into salt-conscious patients, or those who were careful to reduce their daily salt intake, and non-salt-conscious patients. It was found that urinary salt excretion was lower in the salt-conscious group than in the non-salt-conscious group (9.4 +/- 3.8 vs. 10.6 +/- 4.0 g/day, p<0.01), but that urinary salt excretion adjusted for body weight was not significantly different between the two groups (0.16 +/- 0.06 vs. 0.17 +/- 0.07 g/kg/day). Our results suggest that there was no obvious reduction in the actual salt intake in salt-conscious patients, suggesting the importance of monitoring salt intake by 24-h home urine collection and informing patients of their actual salt intake as a means of encouraging the achievement of salt restriction.

[A unique case of recurrent malignant hypertension after removal of an adrenal tumor for primary aldosteronism].

We report here a unique case of recurrent malignant hypertension after the removal of an adrenal tumor for primary aldosteronism. The patient had a history of hypertension for 15 years. In 1995, he developed drug-resistant hypertension with hyperreninemia, hyperaldosteronemia and hypokalemia. He was diagnosed as having primary aldosteronism with a right adrenal tumor. His blood pressure did not normalize and renal dysfunction continued after the adrenalectomy. Although antihypertensive treatment was continued for residual hypertension, he soon refused medication. In 1997, he developed recurrent malignant hypertension. It was considered that the different underlying mechanisms might be attributable to the two episodes of malignant hypertension in this patient.

Long-term variability of urinary salt excretion and blood pressure in hypertensive patients.

We investigated the long-term trend and variability of urinary salt (sodium chloride) excretion in hypertensive patients. Subjects included 186 hypertensive patients (103 women and 83 men, mean age: 58.5±10.5 years) who underwent 10 successful 24-h home urine collections over a mean observation period of 7.7 years. We measured 24-h urinary salt excretion and blood pressure (BP) sequentially at the time of each collection and monitored the long-term trend and variability of urinary salt excretion. BP significantly decreased from 145±16/85±11 mm Hg to 130±12/70±11 mm Hg and was associated with an increased use of antihypertensive drugs. The 24-h urinary salt excretion also decreased from 9.5±3.6 g per day at the first measurement to 8.5±3.2 g per day at the 10th measurement. Urinary salt excretion during the observation period ranged from a minimum value of 5.2±1.8 g per day to a maximum value of 13.4±3.6 g per day with a coefficient of variation of 29.2±8.1%. When subjects were assigned to a low, medium and high salt group based on the tertiles of the first measurement of urinary salt excretion and the tertiles based on the mean value of 10 measurements during the observation period, only 56.2% remained in the same category, suggesting that a single measurement of urinary salt excretion can only predict long-term urinary salt excretion in approximately half of the individuals. In conclusion, urinary salt excretion shows large variability such that a single measurement may not be sufficient to assess salt intake in individuals.

The interpolated projection data estimation method improves the image quality of myocardial perfusion SPECT with a short acquisition time.

OBJECTIVE: The interpolated projection data estimation processing (IPDE) method increases the amount of projection data by interpolation of the projection data. We examined the usefulness of the IPDE method for (201)Tl myocardial perfusion imaging (MPI) single photon emission computed tomography (SPECT) with a short acquisition time. METHODS: Forty patients with suspected ischemic heart disease underwent stress (201)Tl-MPI SPECT. Both stress and delayed images were acquired with 4 cycles of 360° continuous rotation with a 90-direction setting for 14 min. The projection data used for reconstruction were 1) all cycle data (Tl-90-14min), 2) 2 cycles of data (Tl-90-7min), and 3) 2 cycles of data processed using the IPDE method (Tl-180IPDE-7min). This study compared the detection of the perfusion defect by the uptake score and the image quality of (201)Tl-MPI SPECT using the normalized mean square error (NMSE). RESULTS: The uptake score of Tl-180IPDE-7min was significantly more concordant with Tl-90-14min in comparison to the Tl-90-7min (p < 0.05). The NMSE of the Tl-180IPDE-7min (1.85 ± 1.06%) was significantly lower than that of the Tl-90-7min (2.07 ± 1.24%) (p < 0.05). The degree of improvement by the IPDE method was significantly greater for the delayed (201)Tl-MPI SPECT than for the stress (201)Tl-MPI SPECT (p < 0.05). CONCLUSION: The IPDE method improved the image quality and secured the diagnostic ability of (201)Tl-MPI SPECT for a short acquisition time. Furthermore, the IPDE method is a simple software program that does not require any expensive equipment or use advanced algorithms. These results suggest that the IPDE method may be useful as an adjunctive method for shortening the acquisition time of (201)Tl-MPI SPECT.