Universal drug coverage and income-related disparities in glycaemic control.

AIMS: To examine whether income-related disparities in glycaemic control decline after the age of 65 years, when publicly funded universal drug insurance is acquired in Ontario, Canada. METHODS: We conducted a population-based cross-sectional study using linked administrative healthcare databases. Adults with diabetes, aged 40-89 years, with available HbA1c data were included (N = 716 297). Income was based on median neighbourhood household income. Multiple linear regression was used to test for effect modification of age ≥65 years on the relationship between income and HbA1c . RESULTS: There was a significant inverse association between income and HbA1c level. After adjusting for baseline factors, the effect of income on HbA1c level was significantly greater for individuals aged <65 years (mean difference HbA1c for lowest vs highest income group +2.5 mmol/mol, 95% CI +2.3 to +2.7 [+0.23%, 95% CI 0.21 to 0.24]) than for those aged ≥65 years (+1.2 mmol/mol, 95% CI +1.0 to +1.3 [+0.11%, 95% CI 0.10 to 0.12]; P < 0.0001 for interaction). CONCLUSIONS: Despite universal access to healthcare, people with diabetes with lower incomes had significantly worse glycaemic control compared with their counterparts on higher incomes. However, income gradients in glycaemic control were markedly reduced after the age of 65 years, possibly as a result of access to prescription drug coverage.

Metformin and breast cancer stage at diagnosis: a population-based study.

PURPOSE: The objective of the present study was to use a large, population-based cohort to examine the association between metformin and breast cancer stage at diagnosis while accounting for mammography differences. METHODS: We used data from Ontario administrative health databases to identify women 68 years of age or older with diabetes and invasive breast cancer diagnosed from 1 January 2007 to 31 December 2012. Adjusted logistic regression models were used to compare breast cancer stage at diagnosis (stages i and ii vs. iii and iv) between the women exposed and not exposed to metformin. We also examined the association between metformin use and estrogen receptor status, tumour size, and lymph node status in the subset of women for whom those data were available. RESULTS: We identified 3125 women with diabetes and breast cancer; 1519 (48.6%) had been exposed to metformin before their cancer diagnosis. Median age at breast cancer diagnosis was 76 years (interquartile range: 72-82 years), and mean duration of diabetes was 8.8 ± 5.9 years. In multivariable analyses, metformin exposure was not associated with an earlier stage of breast cancer (odds ratio: 0.98; 95% confidence interval: 0.81 to 1.19). In secondary analyses, metformin exposure was not associated with estrogen receptor-positive breast cancer, tumours larger than 2 cm, or positive lymph nodes. CONCLUSIONS: This population-based study did not show an association between metformin use and breast cancer stage or tumour characteristics at diagnosis. Our study considered older women with long-standing diabetes, and therefore further studies in younger patients could be warranted.

Early specialist care for diabetes: who benefits most? A propensity score-matched cohort study.

AIMS: To examine whether early endocrinologist care reduces the risk of cardiovascular complications among newly diagnosed patients with diabetes of differing complexity. METHODS: We conducted a population-based propensity score-matched cohort study using provincial health data from Ontario, Canada. Adults (≥ 30 years) diagnosed with diabetes between 1 April 1998 and 31 March 2006 who received endocrinologist care in the first year of diagnosis were matched to a comparison group receiving primary care alone (N = 79 020) based on propensity scores and medical complexity (assigned using information on chronic conditions). Individuals were followed for 3- and 5-year outcomes, including non-fatal acute myocardial infarction or coronary heart disease death (primary endpoint), major cardiovascular events (acute myocardial infarction, stroke) or all-cause death, amputation and end-stage renal disease. RESULTS: Among medically complex patients, early endocrinologist care was associated with a lower 3-year incidence of the primary endpoint (hazard ratio 0.89, 95% CI 0.78-1.01) and major cardiovascular events or all-cause death (hazard ratio 0.91, 95% CI 0.85-0.97). These effects persisted after accounting for a higher incidence of end-stage renal disease on follow-up and were greatest in those with ≥ 3 visits to an endocrinologist (primary endpoint: hazard ratio 0.69, 95% CI 0.56-0.86 and 0.61, 95% CI 0.45-0.82, for unadjusted and end-stage renal disease adjusted analyses, respectively). In contrast, no benefit was observed in the non-medically complex subgroup. Overall effects were similar at 5 years. CONCLUSIONS: Early endocrinologist care is associated with a lower incidence of cardiovascular events and death among newly diagnosed patients with diabetes who have comorbid medical conditions.

Impact of socio-economic status on breast cancer screening in women with diabetes: a population-based study.

AIMS: There is evidence to suggest that mammography rates are decreased in women with diabetes and in women of lower socio-economic status. Given the strong association between low socio-economic status and diabetes, we explored the extent to which differences in socio-economic status explain lower mammography rates in women with diabetes. METHODS: A population-based retrospective cohort study in Ontario, Canada, of women aged 50 to 69 years with diabetes between 1999 and 2010 age matched 1:2 to women without diabetes. Main outcome measure is the likelihood of at least one screening mammogram in women with diabetes within a 36-month period, starting as of either 1 January 1999, their 50th birthday, or 2 years after diabetes diagnosis--whichever came last. Outcomes were compared with those in women without diabetes during the same period as their matched counterparts, adjusting for socio-economic status based on neighbourhood income and other demographic and clinical variables. RESULTS: Of 504,288 women studied (188,759 with diabetes, 315,529 with no diabetes), 63.8% had a screening mammogram. Women with diabetes were significantly less likely to have a mammogram after adjustment for socio-economic status and other factors (odds ratio 0.79, 95% CI 0.78-0.80). Diabetes was associated with lower mammogram use even in women from the highest socio-economic status quintile (odds ratio 0.79, 95% CI 0.75-0.83). CONCLUSIONS: The presence of diabetes was an independent barrier to breast cancer screening, which was not explained by differences in socio-economic status. Interventions that target patient, provider, and health system factors are needed to improve cancer screening in this population.

Incidence of diabetes among postmenopausal breast cancer survivors.

AIMS/HYPOTHESIS: Evidence is emerging of an association between breast cancer and diabetes; however, it is uncertain whether diabetes incidence is increased in postmenopausal breast cancer survivors compared with women without breast cancer. The objective of this study was to determine whether postmenopausal women who develop breast cancer have a higher incidence of diabetes than those who do not develop breast cancer. METHODS: We used population-based data from Ontario, Canada to compare the incidence of diabetes among women with breast cancer, aged 55 years or older, from 1996 to 2008, with that of age-matched women without breast cancer. We used Cox proportional hazard models to estimate the effect of breast cancer on the cause-specific hazard of developing diabetes overall and in the subgroup of women who received adjuvant chemotherapy. RESULTS: Of 24,976 breast cancer survivors and 124,880 controls, 9.7% developed diabetes over a mean follow-up of 5.8 years. The risk of diabetes among breast cancer survivors compared with women without breast cancer began to increase 2 years after diagnosis (HR 1.07 [95% CI, 1.02, 1.12]), and rose to an HR of 1.21 (95% CI, 1.09, 1.35) after 10 years. Among those who received adjuvant chemotherapy (n = 4,404), risk was highest in the first 2 years after diagnosis (HR 1.24 [95% CI 1.12, 1.38]) and then declined. CONCLUSIONS/INTERPRETATION: We found a modest increase in the incidence of diabetes among postmenopausal breast cancer survivors that varied over time. In most women the risk began to increase 2 years after cancer diagnosis but the highest risk was in the first 2 years in those who received adjuvant therapy. Our study suggests that greater diabetes screening and prevention strategies among breast cancer survivors may be warranted.

The risk of falls on initiation of antihypertensive drugs in the elderly.

SUMMARY: Antihypertensive drugs are associated with an immediate increased falls risk in elderly patients which was significant during the first 14 days after receiving a thiazide diuretic, angiotensin-converting enzyme inhibitor, angiotensin II receptor blocker, calcium channel blocker, or beta-adrenergic blocker. Fall prevention strategies during this period may prevent fall-related injuries. INTRODUCTION: The purpose of this study is to evaluate if initiation of the common antihypertensive drugs is associated with the occurrence of falls. METHODS: This population-based self-controlled case series study used healthcare administrative databases to identify new users of antihypertensive drugs in the elderly aged 66 and older living in Ontario, Canada who suffered a fall from April 1, 2000 to March 31, 2009. The risk period was the first 45 days following antihypertensive therapy initiation, further subdivided into 0-14 and 15-44 days with control periods before and after treatment in a 450-day observation period. We calculated the relative incidence (incidence rate ratio, IRR), defined as the rate of falls in the risk period compared to falls rate in the control periods. RESULTS: Of the 543,572 new users of antihypertensive drugs among community-dwelling elderly, 8,893 experienced an injurious fall that required hospital care during the observation period. New users had a 69 % increased risk of having an injurious fall during the first 45 days following antihypertensive treatment (IRR = 1.69; 95 % CI, 1.57-1.81). This finding was consistent for thiazide diuretics, angiotensin-converting enzyme inhibitors, calcium channel blockers, and beta-adrenergic blockers but not angiotensin II receptor antagonists. There was also an increased falls risk during the first 14 days of antihypertensive drug initiation (IRR = 1.94; 95 % CI, 1.75-2.16), which was consistent for all antihypertensive drug classes. CONCLUSIONS: This study suggests that initiation of antihypertensive drugs is a risk factor for falls in the elderly. Fall prevention strategies during this period may reduce injuries.

Using the Johns Hopkins' Aggregated Diagnosis Groups (ADGs) to predict 1-year mortality in population-based cohorts of patients with diabetes in Ontario, Canada.

AIMS: There are limited validated methods to ascertain comorbidities for risk adjustment in ambulatory populations of patients with diabetes using administrative health-care databases. The objective was to examine the ability of the Johns Hopkins' Aggregated Diagnosis Groups to predict mortality in population-based ambulatory samples of both incident and prevalent subjects with diabetes. METHODS: Retrospective cohorts constructed using population-based administrative data. The incident cohort consisted of all 346,297 subjects diagnosed with diabetes between 1 April 2004 and 31 March 2008. The prevalent cohort consisted of all 879,849 subjects with pre-existing diabetes on 1 January, 2007. The outcome was death within 1 year of the subject's index date. RESULTS: A logistic regression model consisting of age, sex and indicator variables for 22 of the 32 Johns Hopkins' Aggregated Diagnosis Group categories had excellent discrimination for predicting mortality in incident diabetes patients: the c-statistic was 0.87 in an independent validation sample. A similar model had excellent discrimination for predicting mortality in prevalent diabetes patients: the c-statistic was 0.84 in an independent validation sample. Both models demonstrated very good calibration, denoting good agreement between observed and predicted mortality across the range of predicted mortality in which the large majority of subjects lay. For comparative purposes, regression models incorporating the Charlson comorbidity index, age and sex, age and sex, and age alone had poorer discrimination than the model that incorporated the Johns Hopkins' Aggregated Diagnosis Groups. CONCLUSIONS: Logistical regression models using age, sex and the John Hopkins' Aggregated Diagnosis Groups were able to accurately predict 1-year mortality in population-based samples of patients with diabetes.

Effect of subsequent pregnancies on the risk of developing diabetes following a first pregnancy complicated by gestational diabetes: a population-based study.

AIMS: Women with gestational diabetes mellitus have a high risk of developing Type 2 diabetes, secondary to post-partum progression of the chronic pancreatic ß-cell defect that underlies their presenting with dysglycaemia in pregnancy. Insulin-sensitizing therapy can decrease this risk of Type 2 diabetes, partly by offloading the secretory demand placed on the ß-cells. Conversely, however, it is not known whether the considerable secretory demands posed by the physiologic insulin resistance of a subsequent pregnancy could accelerate the progression to Type 2 diabetes. Thus, we sought to determine whether subsequent pregnancies are associated with the risk of developing diabetes following gestational diabetes. METHODS: Using a population-based administrative database, we identified all women in Ontario, Canada, whose first pregnancy was between April 2000 and March 2007 and was complicated by gestational diabetes (n = 16,817). This cohort was followed for a median 4.5 years for subsequent pregnancies and the development of diabetes. RESULTS: During follow-up, 2731 women (16.2%) developed diabetes. Gestational diabetes recurred in 41.5% of subsequent pregnancies. Interestingly, after covariate adjustment, a subsequent pregnancy was associated with a reduced risk of diabetes (adjusted hazard ratio (HR) = 0.68, 95%CI 0.60-0.76; P < 0.0001). Specifically, whereas each subsequent gestational diabetes pregnancy was associated with a modestly increased risk of diabetes (adjusted HR = 1.16, 95%CI 1.01-1.34; P = 0.03), each non-gestational diabetes pregnancy was associated with a significantly reduced risk of diabetes (adjusted HR=0.34, 95%CI 0.27-0.41; P < 0.0001). CONCLUSIONS: A subsequent pregnancy is not necessarily associated with an increased risk of Type 2 diabetes following gestational diabetes. Instead, the absence of recurrent gestational diabetes in a subsequent pregnancy may identify a lessened risk of developing Type 2 diabetes in this high-risk patient population.

New use of rosiglitazone decreased following publication of a meta-analysis suggesting harm.

AIMS: It is uncertain whether meta-analyses lead to changes in prescribing practices. We studied trends in the prescribing of glucose-lowering therapy before and after the publication of a meta-analysis suggesting harm from rosiglitazone. METHODS: We examined the prescription records of all residents of Ontario, Canada, aged > or = 66 years. For each week between January and December 2007, we identified new users of five categories of glucose-lowering medications: rosiglitazone, pioglitazone, metformin, glibenclamide (glyburide) and insulin. The effect of the meta-analysis was assessed using interventional autoregressive integrated moving-average models. RESULTS: Following the release of the meta-analysis, there was a sudden decline in new users of rosiglitazone (P = 0.01), mirrored by a nearly identical but transient increase in new users of pioglitazone (P < 0.001). There was also a net decline in new users of thiazolidinediones as a class (P < 0.001). The number of new users of other glucose-lowering medications did not change. CONCLUSIONS: A highly-publicized meta-analysis regarding rosiglitazone's potential harms led to an abrupt decline in new users of the drug, as well as a transient surge in new use of pioglitazone.

Continental variations in IgA nephropathy among Asians.

BACKGROUND/AIMS: Local variations in patient demographics and medical practice can contribute to differences in renal outcomes in patients with IgA nephropathy. We report the experiences of two groups of Asians with IgA nephropathy across continents. MATERIALS AND METHODS: We retrospectively examined two cohorts of Asian patients with IgA nephropathy from The King Chulalongkorn Memorial Hospital registry, Thailand (1994 - 2005), and The Metropolitan Toronto Glomerulonephritis registry, Canada (1975 - 2006), and compared their baseline characteristics. Slope of estimated glomerular filtration rate (eGFR) in each group was approximated using separate repeated measures regression models for each country. RESULTS: There were 152 Canadian and 76 Thai patients. At the time of first presentation, Thai patients were more likely to be female (63.2 vs. 44.1%, p = 0.01), have less baseline proteinuria (1.2 vs. 1.7 g/d, p = 0.08) and more likely to receive angiotensin-converting enzyme inhibitors (ACE-I) or angiotensin receptor blockers (ARB) (64.0 vs. 15.2%, p < 0.01), or prednisone (41.3 vs. 4.6%, p < 0.01). The annual change in estimated glomerular filtration rate (eGFR) for the Thai and Canadian groups were -0.82 ml/min/1.73 m2/year and -3.35 ml/min/1.73 m2/year, respectively, after adjustment for age, sex, mean arterial pressure (MAP), proteinuria, body mass index, Haas histological grade, chronicity scores and baseline medications. CONCLUSIONS: Although disease severity was similar among IgA nephropathy patients in Canada and Thailand, more Thai patients were on ACE-I/ARB or prednisone therapy at baseline. Further prospective research is needed to explore international differences in demographic and environmental factors, health resources, and disease management to determine how they may impact long-term outcomes in Asians with IgA nephropathy.

A systematic review of propensity score methods in the acute care surgery literature: avoiding the pitfalls and proposing a set of reporting guidelines.

BACKGROUND: Propensity score methods are techniques commonly employed in observational research to account for confounding when estimating the effects of treatments and exposures. These methods have been increasingly employed in the acute care surgery literature in an attempt to infer causality; however, the adequacy of reporting and the appropriateness of statistical analyses when using propensity score matching remain unclear. OBJECTIVES: The goal of this systematic review is to assess the adequacy of reporting of propensity score methods, with an emphasis on propensity score matching (to assess balance and the use of appropriate statistical tests), in acute care surgery (ACS) studies and to provide suggestions for improvement for junior investigators. METHODS: We searched three databases, and other relevant literature (from January 2005 to June 2015) to identify observational studies within the ACS literature using propensity score methods (PROSPERO No: CRD42016036432). Two reviewers extracted data and assessed the quality of the studies retrieved by reviewing the adequacy of both overall reporting and of the propensity score matching methods used. RESULTS: A total of 49/71 (69%) of studies adequately reported propensity score methods overall. Matching was the most common propensity score method used in 46/71 (65%) studies, with 36/46 (78%) studies reporting matching methods adequately. Only 19/46 (41%) of matching studies reported the balance of baseline characteristics between treated and untreated subjects while 6/46 (13%) used correct statistical methods to assess balance. There were 35/46 (76%) of matching studies that explicitly used statistical methods appropriate for the analysis of matched data when estimating the treatment effect and its statistical significance. CONCLUSION: We have proposed reporting guidelines for the use of propensity score methods in the acute care surgery literature. This is to help investigators improve the adequacy of reporting and statistical analyses when using observational data to estimate effects of treatments and exposures.

Emergency department visits and unplanned hospitalizations in the treatment period for head and neck cancer patients treated with curative intent: A population-based analysis.

BACKGROUND: Mucosal head and neck squamous cell cancers are often managed with multimodality treatment which can be associated with significant toxicity. The objective of this study was to assess emergency department visits and unplanned hospitalizations for these patients during and immediately after their treatment. METHODS: A cohort of patients treated for head and neck squamous cell carcinoma was developed using administrative data. Emergency department visits and hospitalizations in the 90-day post-treatment period was determined. If a second treatment was initiated prior to the completion of 90 days, the attributable risk period was changed to the second treatment. RESULTS: Cohort of 3898 patients (1312 larynx/hypopharynx; 2586 oral cavity/oropharynx) from 2008 to 2012. The number of unplanned hospitalizations or ED visits (per 100 patient days) were 0.69 for surgery, 0.78 for surgery followed by concurrent chemoradiotherapy (CCRT), 0.55 for surgery followed by radiotherapy, 0.86 for CCRT, and 0.50 for radiation. Patients receiving CCRT had a statistically higher likelihood of treatment period events. The larynx/hypopharynx cancer subsite, higher comorbidity and more advanced stage of disease were all independent predictors of events. CONCLUSIONS: Patients undergoing treatment for head and neck cancer have significant unplanned hospitalizations and visits to the emergency department in the treatment period. Rates are higher in patients receiving CCRT. Quality improvement interventions should be used to improve these rates.

Age-social stratification designs had a negligible impact on income-mortality associations.

OBJECTIVES: Age-social stratification has been used to offset socioeconomic status (SES) misclassification due to cohort effects. This study was to evaluate whether age-income stratification designs generate comparable income-mortality associations as those whose income rankings are based on absolute thresholds. STUDY DESIGN AND SETTING: Using self-reported income as our SES variable, and mortality as our outcome measure, the impact of age-social stratification was examined in two distinct cohorts: one with acute myocardial infarction (AMI) (n=3,138), and the second free of cardiovascular disease (n=15,115). Age-adjusted income-mortality associations were compared between age-social stratification techniques, which used "age-relative" income thresholds and "absolute" income thresholds whose ranks were independent of patient age. RESULTS: In both cohorts, crude mortality inversely correlated with age and income. Techniques using "age-relative" income thresholds yielded similar adjusted odds ratio for mortality as did those that used "absolute" income threshold methods (differences in adjusted odds ratios [+/-95% confidence interval (CI)] between "absolute" and "age-relative" classifications for highest vs. lowest income tertiles: -0.05 [-0.24, 0.12] among patients with AMI and 0.05 [-0.03, 0.13] among patients without cardiovascular disease). CONCLUSION: More complex designs incorporating age-social stratification techniques generate similar income-mortality associations as more simplified approaches, which classified SES using absolute income thresholds.

Accuracy of administrative health data for the diagnosis of upper gastrointestinal diseases.

BACKGROUND: The use of administrative health data is increasingly common for the study of various medical and surgical diseases. The validity of diagnosis codes for the study of benign upper gastrointestinal disorders has not been well studied. METHODS: The authors abstracted the charts for 590 adult patients who underwent upper gastrointestinal endoscopy between January 1, 2000 and June 30, 2001 in Toronto, Ontario, Canada. Clinical diagnoses from medical records were compared with International Classification of Diseases Version 9 (ICD-9) codes in electronic hospital discharge abstracts. The primary analysis aimed to determine the sensitivity, specificity, and positive predictive value (PPV) of a most responsible "esophagitis" diagnosis code for the prediction of esophagitis. Secondary analyses determined the performance characteristics of the diagnostic codes for esophageal ulcer, esophageal stricture, gastroesophageal reflux disease (GERD), gastritis, gastric ulcer, and duodenal ulcer. RESULTS: The authors linked 500 patient records to electronic discharge abstracts. When listed as the most responsible diagnosis for admission, the ICD-9 codes for esophagitis showed a sensitivity of 46.79%, a specificity of 98.83%, and a PPV of 94.81%. When listed as a secondary diagnosis, the ICD-9 codes showed a sensitivity of 70.51%, a specificity of 97.67%, and a PPV of 93.22%. The diagnostic properties of ICD-9 codes for GERD (most responsible, secondary) were as follows: sensitivity (56.10%, 78.66%), specificity (98.51%, 96.73%), and PPV (94.84%, 92.14%). CONCLUSIONS: The ICD-9 diagnosis codes for benign upper gastrointestinal diseases are highly specific and associated with strong PPVs, but have poor sensitivity.

Biology or bias: practice patterns and long-term outcomes for men and women with acute myocardial infarction.

OBJECTIVES: The goal of our study was to examine how age and gender affect the use of coronary angiography and the intensity of cardiac follow-up care within the first year after acute myocardial infarction (AMI). Another objective was to evaluate the association of age, gender and treatment intensity with five-year survival after AMI. BACKGROUND: Utilization rates of specialized cardiac services inversely correlate with age. Gender-specific practice patterns may also vary with age in a manner similar to known age-gender survival differences after AMI. METHODS: Using linked population-based administrative data, we examined the association of age and gender with treatment intensity and long-term survival among 25,697 patients hospitalized with AMI in Ontario between April 1, 1992, and December 31, 1993. A Cox proportional hazards model was used to adjust for socioeconomic status, illness severity, attending physician specialty and admitting hospital characteristics. RESULTS: After adjusting for baseline differences, the relative rates of angiography and follow-up specialist care for women relative to men, respectively, fell 17.5% (95% confidence interval [CI], 13.6 to 21.3, p < 0.001) and 10.2% (95% CI, 7.1 to 13.2, p < 0.001) for every 10-year increase in age. Conversely, long-term AMI survival rates in women relative to men improved with increasing age, such that the relative survival in women rose 14.2% (95% CI, 10.1 to 17.5, p < 0.001) for every 10-year age increase. CONCLUSIONS: Gender differences in the intensity of invasive testing and follow-up care are strongly age-specific. While care becomes progressively less aggressive among older women relative to men, survival advantages track in the opposite direction, with older women clearly favored. These findings suggest that biology is likely to remain the main determinant of long-term survival after AMI for women.

Development and validation of the Ontario acute myocardial infarction mortality prediction rules.

OBJECTIVES: To develop and validate simple statistical models that can be used with hospital discharge administrative databases to predict 30-day and one-year mortality after an acute myocardial infarction (AMI). BACKGROUND: There is increasing interest in developing AMI "report cards" using population-based hospital discharge databases. However, there is a lack of simple statistical models that can be used to adjust for regional and interinstitutional differences in patient case-mix. METHODS: We used linked administrative databases on 52,616 patients having an AMI in Ontario, Canada, between 1994 and 1997 to develop logistic regression statistical models to predict 30-day and one-year mortality after an AMI. These models were subsequently validated in two external cohorts of AMI patients derived from administrative datasets from Manitoba, Canada, and California, U.S. RESULTS: The 11-variable Ontario AMI mortality prediction rules accurately predicted mortality with an area under the receiver operating characteristic (ROC) curve of 0.78 for 30-day mortality and 0.79 for one-year mortality in the Ontario dataset from which they were derived. In an independent validation dataset of 4,836 AMI patients from Manitoba, the ROC areas were 0.77 and 0.78, respectively. In a second validation dataset of 112,234 AMI patients from California, the ROC areas were 0.77 and 0.78 respectively. CONCLUSIONS: The Ontario AMI mortality prediction rules predict quite accurately 30-day and one-year mortality after an AMI in linked hospital discharge databases of AMI patients from Ontario, Manitoba and California. These models may also be useful to outcomes and quality measurement researchers in other jurisdictions.

Use of antidepressants among elderly subjects: trends and contributing factors.

OBJECTIVE: The authors assessed changes over time in antidepressant utilization among elderly subjects regarding the prevalence of antidepressant users, shifts in prescription patterns, and related financial implications. METHOD: The authors conducted a population-based study of more than 1.4 million Ontario residents aged 65 years or older. Cross-sectional data regarding annual antidepressant utilization were obtained from administrative databases for 1993 to 1997. Time series analysis was used to assess trends over time and to make future projections. RESULTS: The proportion of antidepressant users increased from 9.3% of the elderly population in 1993 to 11.5% in 1997. Prescriptions for selective serotonin reuptake inhibitors (SSRIs) accounted for 9.6% of antidepressant prescriptions dispensed in the first 30 days of 1993 and 45.1% of those dispensed by the last 30 days of 1997 and were projected to increase to approximately 56% by the end of 2000. Prescriptions for tricyclic antidepressants fell from 79.0% in the first 30 days of 1993 to 43.1% by the last 30 days of 1997 and were projected to decline to approximately 28% by the end of 2000. Annual antidepressant costs (in Canadian dollars) increased by 150%, from $10.8 million in 1993 to $27.0 million in 1997. Population shifts and an increase in the prevalence of antidepressant users accounted for at least 20% of this increase, whereas the prescribing transition from tricyclic antidepressants to SSRIs accounted for at least 61% of the increase. CONCLUSIONS: The introduction of SSRIs has had a substantial financial impact at the drug utilization level. Future research should address the appropriate balancing of the cost of newer agents versus their ostensible advantages.

Return to work after heart transplantation: 12-year follow-up.

BACKGROUND: Current statistics show that 50% of heart transplantation recipients survive 10 years or more. Emphasis on cost containment has renewed interest in the employment status of these long-term survivors. METHODS: We have identified 62 patients operated on at one United Kingdom center and evaluated their employment and clinical status by interview at 1, 5, and 12 years from surgery. RESULTS: Employment pattern was good, with 69%, 69% (of 55 survivors), and 57% (of 35 survivors) of the group working at 1, 5, and 12 years, respectively. Blue-collar work status per se was not a deterrent to employment, but older patients with a poor presurgical work history were less successful in finding work, and trade and legislative restrictions forced some, who were willing and capable of returning to their previous employment, into lower paid, less satisfactory jobs. CONCLUSIONS: Subgroups of patients who are likely to be unemployed can be identified prior to surgery. Steps can be taken prior to surgery to anticipate future problems, and establish realistic employment goals.