The aim of this study was to investigate the prevalence of benzodiazepine and related drug (BZDR) use, especially long-term use, and associated factors among community-dwelling individuals with and without Alzheimer's disease (AD). We utilized data from the MEDALZ-2005 cohort, which includes all community-dwelling individuals diagnosed with AD in Finland at the end of 2005 and matched comparison individuals without AD. Register-based data included prescription drug purchases, comorbidities, and hospital discharge diagnoses. In this study, 24,966 individuals with AD and 24,985 individuals without AD were included. During the 4-year follow-up, we found that 45% (N = 11,312) of individuals with AD and 38% (N = 9534) of individuals without AD used BZDRs. The prevalence of long-term (= 180 days) BZDR use was more common among individuals with AD (30%) than individuals without AD (26%). The median durations of the first long-term use periods of BZDRs were 1.5 and 2 years for individuals with and without AD, respectively. Factors associated with long-term BZDR use included female sex, AD, schizophrenia, bipolar disorder, depression, coronary artery disease, and asthma/chronic obstructive pulmonary disease. The high prevalence of long-term BZDR use among individuals with AD is especially a cause for concern because long-term use may further impair cognition and may be associated with serious adverse events.
Antidepressants are used to treat depression and behavioral symptoms in Alzheimer's disease (AD), although their effectiveness has been questioned and evidence about the risks is accumulating. The objective of this study was to compare antidepressant use among persons with and without AD in Finland.
The Social Insurance Institution of Finland (SII) identified all persons with a verified diagnosis of AD in Finland on December 31, 2005. For each person with AD a comparison person matched for age, sex and region of residence was also identified. Data on reimbursed drug purchases in 2005 were extracted from the Finnish National Prescription Register (FNPR). Conditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for antidepressant use.
The study sample comprised of 28,089 matched pairs of persons with and without AD (mean age 80.0 SD 6.8, 32.2% men).The prevalence of antidepressant use was higher among persons with AD than without AD (29.4% vs. 10.7%, OR = 3.54; 95% CI: 3.38, 3.70). Among the persons with AD, the prevalence of antidepressant use increased with time since AD diagnosis but not with age. Overall, 90.4% of antidepressant users with AD were co-dispensed anti-dementia drugs.
The antidepressant use was three times more prevalent among persons with AD compared to those without. Though the antidepressant selection was largely consistent with clinical practice guidelines, the high prevalence of use warrants further investigation given the uncertain effectiveness and adverse events related to these drugs.