Comorbidities are common in mental health and the relationship between physical and mental health conditions appears to be bidirectional. Having a chronic physical condition like diabetes can increase your risk of depression (by as much as 3 times). Having an enduring mental health problem such as psychosis can take 15-20 years off your life.

In recent years, we have seen a welcome rise in the number of research studies that focus on comorbidities, but there remains a dearth of evidence about multimorbidities, even though a recent systematic review from Fortin et al showed that prevalence is increasing and that it rises steeply with age.

A new systematic review published in the BMJ last week, brings together the evidence for interventions designed to improve outcomes in patients with multimorbidity in primary care and community settings.

The reviewers searched a wide range of sources and found only 10 randomised controlled trials (including a total of 3,407 patients) to include in their analysis. Two RCTs looked at specific comorbidities and the other 8 investigated multimorbidities, mostly in older patients.

The interventions studied all involved multiple components; sometimes focusing on organisational interventions (e.g. case management, enhanced multidisciplinary teamwork) and sometimes on patient-oriented interventions (e.g. self-management, patient education).

Here’s what they found:

• Organisational interventions were more effective if they:
  • Targeted specific risk factors
  • Focused on areas of patient difficulty (e.g. management of medicines)
• Organisational interventions were less effective if they:
  • Had a broader focus (e.g. case management or changes in the delivery of care)
• On the whole, patient-orientated interventions were less effective if they were not linked to healthcare delivery
• One exception was a professional led patient oriented intervention focused on functional difficulties, which was associated with significant improvements including a reduction in mortality in the intervention group
• Two studies of organisational interventions (Bognor and Katon) showed significant improvements in depression related outcomes

The reviewers concluded:

The review indicates that interventions targeted either at specific combinations of common conditions or at specific problems for patients with multiple conditions, may be more effective.

This review really highlights the lack of research studies that investigate how to improve outcomes for patients with multimorbidities. We can only hope that more pragmatic studies are conducted in primary care to help strengthen the evidence-base in this area.

Links

Smith SM, Soubhi H, Fortin M, Hudon C, O’Dowd T. Managing patients with multimorbidity: systematic review of interventions in primary care and community settings. BMJ. 2012 Sep 3;345:e5205. doi: 10.1136/bmj.e5205.

Fortin M, Stewart M, Poitras M-E, Almirall J, Maddocks H. A systematic review of prevalence studies on multimorbidity: toward a more uniform methodology. Ann Fam Med2012;10:142-51.

Bogner HR, de Vries HF. Integration of depression and hypertension treatment: a pilot, randomized controlled trial. Ann Fam Med 2008;6:295-301.

Katon WJ, Lin EHB, Von Korff M, Ciechanowski P, Ludman EJ, Young B, et al. Collaborative care for patients with depression and chronic illnesses. N Engl J Med 2010;363:2611-20.