Aims: To provide posthoc analyses of a clinical trial that reported beneficial effects of medication reviews on health-related quality of life. Specifically, to describe the medication changes with a focus on deprescribing and to explore patient- and medication-related factors that may identify patients most likely to benefit from medication reviews. Methods: Posthoc analyses of data from a pragmatic, nonblinded, randomized clinical trial investigating a medication review intervention (NCT03911934) in 408 geriatric outpatients treated with ≥9 medicines. Results: In the medication review group (n = 196), 26% of the medicines prescribed at baseline were discontinued with 82% still being discontinued after 13 months. The most common reason for discontinuation was lack of indication (72% of discontinuations). The medicines most often discontinued in the medication review group compared with usual care included: metoclopramide (11/15 = 73% discontinued vs. 1/12 = 8% in usual care), acetylsalicylic acid (20/48 = 42% vs. 2/47 = 4%), simvastatin (18/48 = 38% vs. 2/58 = 3%), zopiclone (23/59 = 39% vs. 4/54 = 7%), quinine (9/14 = 64% vs. 6/16 = 38%), citalopram (4/18 = 22% vs. 0/20 = 0%) and tramadol (18/37 = 49% vs. 8/30 = 27%). Factors associated with number of deprescribed medicines included: number of prescribed medicines, Drug Burden Index, patient motivation for medicine changes, and prescriptions of metoclopramide, iron preparations, antidepressants other than selective serotonin reuptake inhibitors, nonsteroidal anti-inflammatory drugs, or drugs for urinary incontinence. Conclusion: Physician-led medication reviews resulted in persistent deprescribing of medicines in older polypharmacy patients treated with ≥9 medicines. Motivation for having their medicine changed, treatment with more medicines, and a higher burden of sedative and anticholinergic medicines characterized the patients most likely to benefit from physician-led medication reviews.