Discussion
cognitive problems, depression, depressed, cognitive impairment
DISORDER, SECONDARY, PHYSICAL ILLNESS, SENSITIVITY
To our knowledge, this is the first study that has examined the impact of face-to-face BA on functioning in depressed older adults. Our results show that, within BA, functioning improved significantly at post-treatment and that this improvement remained until the 12-month follow-up. When compared to TAU, we demonstrated that BA participants show significantly greater improvement at post-treatment, but lost significance at the 12-month follow-up, due to further improvement among patients receiving TAU. Participants in the TAU condition commonly received continued care well beyond the post-treatment mark, while treatment of participants in the BA condition ended around the post-treatment mark, but their levels of functional improvement remained stable in the subsequent year of follow-up.Unfortunately, norm scores for the WHODAS 2.0, indicating the severity of functional limitations, are not available yet. However, compared to a sample of 65- to 85-year-old people with at least one mental disorder, the baseline level of functional limitations of participants in this study was considered high [Sensitivity analyses showed that cognitive impairment moderated the outcomes. The functioning of participants without cognitive impairment improved significantly in BA than in TAU during treatment. For participants with mild cognitive impairment, there was no statistical difference between the effectiveness of BA and TAU. This effect may be explained by the origin of functional impairment in both groups. Functional impairment in the group without cognitive impairment may be mainly caused by depression, and therefore best treated with a focused, short depression-specific treatment such as BA, whereas functional impairment in a cognitively impaired group might be partially explained as a consequence of the cognitive impairment itself [Several studies have shown that healthcare practitioners can be reluctant to prescribe psychotherapy to older adults [These results have some clinical implications. First, GPs should not use age, sex, and education as a means to determine whether BA would be indicated for functional improvement. Our study showed that functioning improved more in BA than in TAU regardless of these factors. Second, cognitive impairment did moderate treatment results. When GPs suspect cognitive problems, a MoCA score under 26 might indicate that BA and TAU are equally effective, regarding functional improvement, whereas participants with a MoCA score of 26 or higher improve more and faster with BA. Choosing a short-term treatment such as BA for this population reduces healthcare costs while accelerating functional and clinical improvement.One previous study investigated the effect of BA on functioning in older adults [This study has several strengths. First, the ecological validity of the study is high. We lowered the threshold for participation by visiting all patients at home and offering at-home assistance with questionnaires. Therefore, we were able to investigate a relatively old and frail group of home-dwelling older adults. Second, we used a state-of-the-art mixed models design which allowed us to investigate the course of symptoms over time. Third, we investigated several important confounders that could have potentially influenced the results.The study also has some limitations. First, while designing the study, functioning was included as a secondary outcome parameter for which the study was not powered. Therefore, the results are exploratory and need to be confirmed by confirmatory research. Second, most of the participants were Caucasian. We do not know how these results generalise among other ethnic groups. Third, we used the self-reported number of medicines prescribed by a doctor for physical illness as a proxy for physical health, but research about the validity of this measure is scarce. Participants might have over- or underreported used medication. However, research shows that older adults do not always consistently use medication as prescribed [