Total mortality among levothyroxine-treated women with atrial fibrillation in Swedish primary health care

Comparison of Incident Cardiovascular Event Rates Between Generic and Brand l-Thyroxine for the Treatment of Hypothyroidism

OBJECTIVE

To determine whether levothyroxine (L-T4) preparation (generic vs brand) affected hospitalization for cardiovascular events.

PATIENTS AND METHODS

We performed a retrospective analysis using a large administrative claims database, OptumLabs Data Warehouse, creating two 1-to-1 propensity score-matched cohorts initiating generic or brand L-T4. Patients were followed for a mean of 1.0±1.2 years (range, 0-9.3 years). We included 87,902 propensity score-matched patients (43,951 patients per cohort) initiating generic or brand L-T4. Variables included in matching were age, sex, race/ethnicity, residence region, selected comorbidities, and Charlson-Deyo comorbidity score. Patients with previous use of any thyroid preparation, amiodarone, or lithium were excluded. Primary outcomes were the event rates for hospitalizations for incident atrial fibrillation, myocardial infarction, congestive heart failure, or stroke.

RESULTS

In the generic L-T4 cohort, 35,242 (80.2%) were women and 7327 (16.7%) were 65 years of age or older; in the brand L-T4 cohort, 34,633 (78.8%) were women and 8092 (18.4%) were 65 years of age or older. We found no differences in event rates (events per 1000 person-years) for 4 outcomes comparing generic and brand L-T4 therapy: (1) atrial fibrillation (1.82 vs 2.19; hazard ratio [HR], 1.22; 95% CI, 0.90-1.65; P=.19); (2) myocardial infarction (2.12 vs 1.83; HR, 0.86; 95% CI, 0.64-1.17; P=.35); (3) congestive heart failure (2.27 vs 2.00; HR, 0.88; 95% CI, 0.66-1.18; P=.41); and (4) stroke (3.10 vs 2.38; HR, 0.77; 95% CI, 0.59-1.00; P=.05). Stratification by age group revealed no differences.

CONCLUSION

In patients with newly treated hypothyroidism, cardiovascular event rates were similar for generic and brand L-T4.

Comparison of Mortality and Nonfatal Cardiovascular Events in Adults With Atrial Fibrillation With Versus Without Levothyroxine Treatment

Levothyroxine has been suggested to be cardiotoxic, but previous studies on the risk of cardiovascular events associated with levothyroxine treatment have been inconclusive. We aimed to study the association between levothyroxine treatment and all-cause mortality as well as cardiovascular events. Study population included all adults (n = 12,283) ≥ 45 years diagnosed with atrial fibrillation (AF) at 75 primary care centers in Sweden in 2001 to 2007, with (n = 1,189; 283 men and 906 women) or without (n = 11,094) levothyroxine treatment. Outcome was defined as all-cause mortality and cardiovascular events, that is, myocardial infarction, ischemic stroke, and congestive heart failure until December 31, 2010. During a mean 5.8 years (standard deviation 2.4 years) of follow-up, a total of 3,954 patients died (32.2%), among whom 92 men (32.5%) and 266 women (29.4%) were treated with levothyroxine. In fully adjusted Cox regression models (age, co-morbidity, socioeconomic factors, and warfarin treatment), a significant association between levothyroxine treatment and lower mortality was found among women (hazard ratio 0.78, 95% confidence interval 0.68 to 0.91), but not among men (hazard ratio 0.87, 95% confidence interval 0.69 to 1.10). In the secondary analysis, levothyroxine treatment was not associated with the risk of myocardial infarction, ischemic stroke, or congestive heart failure (p > 0.05). In conclusion, in a large representative cohort, we found that levothyroxine treatment decreased the mortality risk in women with AF, which suggests that such treatment could be of benefit in this setting.

Neighborhood deprivation and warfarin, aspirin and statin prescription - A cohort study of men and women treated for atrial fibrillation in Swedish primary care

BACKGROUND

We aimed to study differences in the prescribing of warfarin, aspirin and statins to patients with atrial fibrillation (AF) in socio-economically diverse neighborhoods. We also aimed to explore the effects of neighborhood deprivation on the relationship between CHADS2 risk score and warfarin prescription.

METHODS

Data were obtained from primary health care records that contained individual clinical data that were linked to national data on neighborhood of residence and a deprivation index for different neighborhoods. Logistic regression was used to estimate the potential neighborhood differences in prescribed warfarin, aspirin and statins, and the association between the CHADS2 score and prescribed warfarin treatment, in neighborhoods with high, middle (referent) and low socio-economic (SES).

RESULTS

After adjustment for age, socio-economic factors, co-morbidities and moves to neighborhoods with different SES during follow-up, adults with AF living in high SES neighborhoods were more often prescribed warfarin (men odds ratio (OR) (95% confidence interval (CI): 1.44 (1.27-1.62); and women OR (95% CI): 1.19 (1.05-1.36)) and statins (men OR (95% CI): 1.23 (1.07-1.41); women OR (95% CI): 1.23 (1.05-1.44)) compared to their counterparts residing in middle SES. Prescription of aspirin was lower in men from high SES neighborhoods (OR (95% CI): 0.75 (0.65-0.86)) than in those from middle SES neighborhoods. Higher CHADS2 risk scores were associated with higher warfarin prescription which remained after adjustment for neighborhood SES.

CONCLUSIONS

The apparent inequalities in pharmacotherapy seen in the present study call for resource allocation to primary care in neighborhoods with low and middle socio-economic status.

Effects of prescribed antihypertensives and other cardiovascular drugs on mortality in patients with atrial fibrillation and hypertension: a cohort study from Sweden

Although antihypertensive drugs are known to reduce mortality in individuals with hypertension, the effects of different cardiovascular pharmacotherapies on mortality among patients with hypertension and atrial fibrillation (AF) have been less thoroughly explored. To study mortality rates in men and women separately with hypertension and AF prescribed different cardiovascular pharmacotherapies. A cohort of men (n=2809) and women (n=2793) aged >45 years diagnosed with hypertension and AF were selected using patient records. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using Cox regression, with all-cause mortality as the outcome. Analysis was performed on the whole population and after stratification by age and sex. Independent factors were prescribed pharmacotherapies. Adjustments were made for a propensity score comprising age, comorbidities, education and marital status. The higher the number of antihypertensive drugs prescribed, the lower the mortality rate (P-value for trend 0.005). Individuals prescribed 4-5 antihypertensive drugs had a lower risk of mortality than those prescribed 0-1 drugs (HR: 0.62; 95% CI: 0.45-0.86). The HRs for the following drug classes were: loop diuretics 1.39 (95% CI: 1.08-1.78), non-selective β-blockers 0.68 (95% CI: 0.53-0.88), angiotensin receptor blockers 0.75 (95% CI: 0.56-0.99) and statins 0.68 (95% CI: 0.53-0.88). AF patients with hypertension prescribed statins, non-selective β-blockers and angiotensin receptor blockers had low relative mortality risks, suggesting that these prescribed pharmacotherapies were beneficial. This needs to be further explored in other clinical settings.

Effects of prescribed antithrombotics and other cardiovascular pharmacotherapies on all-cause mortality in patients with diabetes and atrial fibrillation - a cohort study from Sweden using propensity score analyses

AIMS

To study mortality rates among patients with diabetes and concomitant atrial fibrillation (AF), prescribed different cardiovascular drugs in primary health care.

METHODS

Study population consisted of men (n = 1319) and women (n = 1094) aged ≥45 years from a database including 75 primary care centres in Sweden. Cox regression analysis, with hazard ratios (HRs), 95% confidence interval (95% CIs) and mortality (years to death) as outcome, and Laplace regression, with difference in time to first 10% mortality (with 95% CI), were performed. Independent variables were prescribed cardiovascular drugs. Regression models were adjusted for a propensity score calculated separately for each prescribed drug class (comprising age, cardiovascular co-morbidities, education, marital status and pharmacotherapy).

RESULTS

Overall mortality was lower in the whole sample for anticoagulants vs no treatment (HR 0.45; 95% CI 0.26-0.77); and among patients < 80 years for anticoagulants vs. antiplatelets (HR 0.44; 95% CI 0.25-0.78); while among individuals aged ≥80 years, antiplatelets (HR 0.47; 95% CI 0.26-0.87) and anticoagulants (HR 0.49; 95% CI 0.24-1.00) vs. no treatment were equally effective. Statins were associated with lower mortality among those <80 years (HR 0.45; 95% CI 0.29-0.71). Laplace regression models in the whole sample, with years to first 10% of total mortality as outcome, were significant for: among patients < 80 years anticoagulants vs. no treatment 2.70 years (95% CI 0.04-5.37), anticoagulants vs. antiplatelets 2.31 years (95% CI 0.84-3.79), and those ≥80 antiplatelets vs. no treatment 1.78 years (95% CI 1.04-2.52).

CONCLUSIONS

Our findings suggest that antiplatelets could exert a beneficial effect among those above 80 years.

Most common diseases diagnosed in primary care in Stockholm, Sweden, in 2011

BACKGROUND

The most commonly reported diagnoses in primary care are useful to identify and meet health care needs in society. We estimated the rates of the most common diagnoses in primary health care in total and also by gender.

METHODS

This was a cross-sectional study including all 2.0 million inhabitants living in Stockholm County, Sweden, on 1 January 2009. Data on all health care appointments made in primary care in 2011 and during 2009-11 were extracted from the Stockholm County Council data warehouse VAL (Vårdanalysdatabasen; Stockholm regional health care data warehouse). Primary care data were analysed by underlying population and age. Appropriate specialist open care and inpatient data were used for comparison.

RESULTS

The five most common diagnoses in primary care (in 2011) were acute upper respiratory tract infections (6.0% of the population), essential hypertension (5.6%), coughing (2.6%), dorsalgia (2.6%) and acute tonsillitis (2.4%). Female-to-male ratios were higher for 27 of the 30 most common diagnoses, the exceptions being type 2 diabetes, unspecified types of diabetes and multiple wounds.

CONCLUSIONS

The 30 most common diagnoses in primary care reflect the complexity of disorders cared for in the first line of health care. Knowledge of these patterns is important when aiming at using primary health care resources in a proper way.

High prevalence of diagnosis of diabetes, depression, anxiety, hypertension, asthma and COPD in the total population of Stockholm, Sweden - a challenge for public health

Background

There is limited knowledge on the prevalence of disease in total populations. Such studies have historically been difficult to conduct but the development of health data registers has facilitated large-scale studies on recorded diagnoses in entire regions. The aim of this study was to analyze the prevalence of diagnosis of six common diseases in the Swedish capital region.

Methods

The study population included all living persons who resided in Stockholm County, Sweden, on December 31^st 2011 (N = 2 093 717). Information on all consultations between 2007 and 2011 was obtained from primary health care, specialist outpatient care and inpatient care. Prevalence was defined as the proportion of individuals with a recorded diagnosis of diabetes, depression, anxiety disorders, hypertension, asthma and chronic obstructive pulmonary disease during the five year period, respectively. Analyses were done by age and gender.

Results

Hypertension had the highest five-year prevalence (12.2%), followed by depression (6.6%), diabetes mellitus (6.2%), asthma (5.9%), anxiety disorders/phobia (4.8%), and COPD (1.8%). Diabetes was more common in men (5.3% of women and 7.1% of men) while depression (8.7% in women and 4.4% in men) and anxiety (6.3% in women and 3.4% in men) were considerably more common in women. Smaller gender differences were also found for hypertension (13.0% in women and 11.4% in men), asthma (6.4% in women and 5.4% in men) and COPD (2.1% in women and 1.6% in men). Diabetes, hypertension and COPD increased markedly with age, whereas anxiety, depression and asthma were fairly constant in individuals above 18 years. During one year of observation, more than half of all patients had only been diagnosed in primary health care, with hypertension being the diagnosis with the largest proportion of patients only identified in primary health care (70.6%).

Conclusion

The prevalence of common diseases in the population can be estimated by combining data gathered during consecutive years from primary care, specialist outpatient care and inpatient care. However, accuracy of disease prevalence is highly dependent on the quality of the data. The high prevalence of the six diagnoses analysed in this study calls for preventive action to minimize suffering and costs to society.

Effect of cardiovascular drug classes on all-cause mortality among atrial fibrillation patients treated in primary care in Sweden: a cohort study

BACKGROUND

Risk factors for stroke are well known in atrial fibrillation (AF) patients, while less is known on the effect of these factors on total mortality.

OBJECTIVE

Our aim was to study the impact of cardiovascular drug classes on mortality in AF patients treated in primary care.

METHODS

The study population was chosen based on patient data from 75 primary care centres in Sweden compiled in a database. Individuals diagnosed with AF who were older than 45 years were enrolled (n = 12,302, of whom 6,660 were men). Cox regression analysis with mortality (years to death) as outcome was conducted in the men and women separately, as well in the age categories <80 and ≥ 80 years, with cardiovascular drugs as independent factors, and age, cardiovascular diagnoses and educational level as covariates.

RESULTS

Lower mortality was shown for anticoagulant treatment among men, both younger (<80 years) [adjusted hazard ratio (HR) 0.43, 95 % confidence interval (CI) 0.31-0.61] and older (≥ 80 years) (adjusted HR 0.47, 95 % CI 0.32-0.69), and among younger women (adjusted HR 0.46, 95 % CI 0.29-0.74), and for antiplatelet treatment in older men (adjusted HR 0.51, 95 % CI 0.35-0.74). Treatment with thiazides was associated with lower mortality among younger men (adjusted HR 0.68, 95 % CI 0.48-0.96), older men (adjusted HR 0.67, 95 % CI 0.46-0.98) and older women (adjusted HR 0.70, 95 % CI 0.52-0.94). Statins were associated with lower mortality among younger patients, in both men (adjusted HR 0.47, 95 % CI 0.32-0.68) and women (adjusted HR 0.54, 95 % CI 0.35-0.82).

CONCLUSIONS

The differences in age and gender patterns need further exploration.