Depression 2 to 3 Times More Likely in MS Patients Than Others, Study Finds

A likelihood of depression is two to three times higher in multiple sclerosis (MS) patients in the U.S. and U.K. than in similar groups of people in these countries without the disease, a study reported.

This risk was also “most evident in the first five years after MS diagnosis” among people identified via databases in both countries, the researchers wrote.

The study, “Incident depression in patients diagnosed with multiple sclerosis: a multi‐database study,” was published in the European Journal of Neurology.

Research indicates that about one-third of newly diagnosed MS patients are depressed, and up to 60% will develop depression at any time after their diagnosis.

“However, the rate of new depression [cases] after MS diagnosis and during disease progression is not well known,” the researchers wrote.

A research team in the U.S. analyzed data from two large U.S. and U.K. databases containing information on people with and without this disease.

Data from these two sources — the U.S. Department of Defense (US-DOD) military healthcare system and the U.K. Clinical Practice Research Datalink GOLD (UK-CPRD) — identified people diagnosed with MS between 2001–16 (UK-CPRD), and 2004–17 (US-DOD).

Investigators then matched each patient with up to 10 people without MS of the same age, sex, and geographical region who served as controls. Neither patients nor controls had a history of previous treatment for depression.

They then assessed the number of cases of treated for depression following MS diagnosis, and calculated the incidence rates and incidence rate ratios of depression in both groups.

Incidence rate is a frequency measure that reflects the incidence a particular disease has on a specific group of people within a given period of time. Incidence rate ratio is the ratio (quantitative relation between two amounts) between two  incidence rates; it can be used to assess the relative risk a specific group of people have of developing a condition compared to another group that serves as a reference point.

A total of 6,820 patients in the US-DOD database were matched with 58,419 non-patients, and 5,456 patients in the UK‐CPRD matched with 45,712 people without MS.

Relative to people without MS, the incidence rate ratio for depression in patients was about two- to threefold higher: 3.20 in the US-DOD group, and 1.90 in the UK-CPRD group.