Newly observed KD occurred in 14,713 patients. No regimen had significantly lower risk of KDs than “No drug”. The HR estimates ranged 0.86–2.66 for “all” KDs and 0.87–5.30 for “severe” KDs. As additional drugs were combined to compare more complex polypharmacies, higher HRs were consistently observed. Most regimens containing lithium, MSAs, or antipsychotics had a higher risk than “No drug” (p < 0.05). The risk for “all” and “severe” KDs was highest respectively on monoamine oxidase inhibitors (MAOIs) (HR = 2.66, p = 5.73 × 10−5), and a lithium-containing four-class combination (HR = 5.30, p = 2.46 × 10−9). The HR for lithium monotherapy was 1.82 (p = 4.73 × 10−17) for “severe” KDs.
Highlights:
• No drug regimen had a significantly lower risk for kidney disorders than “No drug”.
• Monoamine oxidase inhibitors had markedly high kidney disorders risk estimates.
• Lithium had a 1.27–1.82-fold higher risk of kidney disorders than “No drug”.
• Polypharmacy often had higher kidney disorder risk than monotherapy.