Investigating the link between Japanese Anticholinergic Risk Scale and laxative prescription in older adults: A cross-sectional study of 9,838 patients using dispensing claims from community pharmacies

Anticholinergic medications can cause constipation in older adults. The Japanese Anticholinergic Risk Scale (JARS), released in May 2024, is not yet sufficiently validated clinically. We examined the association between total anticholinergic burden based on JARS and laxative prescriptions. This cross-sectional study utilized community pharmacy dispensing claims for outpatients aged ≥ 65 years who were registered with a family pharmacist between November 1 and December 31, 2024. Chronic medication use was defined as prescriptions totaling ≥ 28 days during the study period. The primary analysis focused on patients receiving 5-9 concomitant chronic medications. Among the 9,838 patients (mean age 81.1 ±7.3 years; 61.1% female), 39.4%, 33.2%, 14.7%, 7.0%, 3.1%, and 2.5% demonstrated JARS scores of 0, 1, 2, 3, 4, and ≥ 5, respectively. Compared with JARS = 0, adjusted odds ratios (aORs) for laxative prescriptions were 0.85 (95% confidence interval [CI]: 0.76 -0.94, <i>p</i> = 0.003) for JARS = 1; 0.79 (0.69-0.91, <i>p</i> = 0.001) for JARS = 2; 0.94 (0.79-1.13, <i>p</i> = 0.537) for JARS = 3; 1.20 (0.93-1.55, <i>p</i> = 0.153) for JARS = 4; and 1.64 (1.24-2.16, <i>p</i> < 0.001) for JARS ≥ 5. This indicated a stepwise pattern with positive association at the highest burden. Furthermore, use of a drug rated 3 on the JARS revealed association with higher odds of laxative prescription (aOR: 1.71, 95% CI: 1.38-2.12, <i>p</i> < 0.001). Both a total JARS burden ≥ 5 and drugs rated 3 on the JARS were significantly associated with laxative prescribing.