Drug Combinations for Mood Disorders and Physical Comorbidities That Need Attention: A Cross-Sectional National Database Survey

Introduction This study investigated combined prescriptions of drugs for mood disorders and physical comorbidities that need special attention in the light of frequent physical comorbidities in patients with mood disorders. Methods We used the claims sampling data of 581,990 outpatients in January 2015 from the National Database of Health Insurance Claims and Specific Health Checkups of Japan. Fisher's exact test was performed to compare the prescription rates of non-steroidal anti-inflammatory drugs (NSAIDs), loop/thiazide diuretics, angiotensin-converting enzyme inhibitors, and/or angiotensin II receptor blockers between lithium users and age- and sex-matched non-lithium users; NSAIDs, antiplatelet drugs, and/or anticoagulants between selective serotonin reuptake inhibitor (SSRI)/serotonin-noradrenaline reuptake inhibitor (SNRI) users and non-users; warfarin between mirtazapine users and non-users; and the proportions of patients in the two groups with a diagnosis of somatic conditions for which these medications were indicated and actually received them. A Bonferroni corrected p-value of<0.05/3 was considered statistically significant. Results Prescriptions of the above-mentioned medications were less frequent in lithium and mirtazapine users and comparable in SSRI/SNRI users, compared to non-users (18.3 vs. 31.9%, p=7.6×10 ^-10; 0.78 vs. 1.65%, p=0.01; 23.1 vs. 24.1%, p=0.044). In a subgroup of patients with somatic diseases for which these medications were indicated, the prescription rates were comparable in lithium and mirtazapine users and higher in SSRI/SNRI users compared to non-users (28.0 vs. 29.4%, p=0.73; 4.7 vs. 7.4%, p=0.28; 35.6 vs. 33.4%, p=0.0026). Discussion Pharmacotherapy with drugs for mood disorders and physical comorbidities that require attention was commonly observed in clinical practice.