Adults with chronic cough experience a disproportionate burden of depressive symptoms and have an increased risk of recurrent depression, according to a study published in ERJ Open Research.
The study authors also found specifically adults with chronic cough that cannot be explained by a respiratory disease experience a more significant burden of depressive symptoms.
“Moreover, in individuals who have a history of depression, chronic cough increases the risk of recurrent depressive events,” they noted. “This emphasises the importance of screening for depression in patients with chronic cough.”
To better understand the association between chronic cough and prevalent, incident, and recurrent depression, the authors used data from a cohort within the prospective population-based Rotterdam Study, which studied epidemiology of chronic diseases among middle-aged and older adultsin a specific district in the Netherlands.
Researchers defined chronic cough as daily coughing for at least 3 months, and used the Center for Epidemiologic Studies Depression scale, clinical interviews, and medical records to evaluate depression.
The cohort included 5877 participants aged 45 years and older. Most (58.9%) were female and the mean (SD) age was 72.3 (7.9) years. Less than a quarter (23.5%) used angiotensin-converting enzyme inhibitors and 13.9% were current smokers at time of data collection.
At baseline, 1884 (32.1%) participants had at least 1 comorbidity, including—from most to least prevalent in this cohort—gastroesophageal reflux disease, asthma, chronic obstructive pulmonary disease, heart failure, diabetes, chronic rhinosinusitis, and lung cancer.
Further, 13% of participants reported clinically relevant depressive symptoms and 21.9% reported a history of depression.
At baseline, adults aged 45 years and older with chronic cough reported more depressive symptoms than adults without chronic cough.
Over 37,287 person-years, 900 adults who completed follow-up developed depressive symptoms (670), a depressive syndrome (112), or a major depressive disorder (118).
Further, chronic cough was associated with an increased risk of depression among participants with a history of depression (HR, 1.45; 95% CI, 1.13-1.84), but not among participants without a history of depression (HR, 0.91; 95% CI, 0.68-1.22).
After stratifying for history of depression, the authors found that chronic cough was only associated with an increased risk of specifically recurrent depression in participants with a history of depression (HR, 1.45; 95% CI, 1.13-1.84).
Chronic cough was particularly associated with the development of depressive symptoms among adults whose chronic cough could not be explained by a known respiratory disease.
“Although this might be explained in part by more power in the analyses including those with chronic cough not explained by respiratory disease, we also see substantially larger effect sizes for the association of chronic cough not explained by a known respiratory disease and depression,” the authors explained, adding that this is consistent with a prior study.
According to the authors, this association could be neurobiological.
They first cited increased neural activity in the periaqueductal gray—a region in the brain involved in the emotional processing of stress and pain—among patients with cough hypersensitivity.
“Furthermore, the psychological determinants of chronic cough and its associated negative social effects highlight the potential concerted role of psychosocial factors on depressive events in chronic cough patients,” the authors said. “In particular, cough-related psychosocial problems, such as altered social identity, social embarrassment and isolation, preoccupation and attentional focus and obsessive and unsuccessful attempts to suppress cough have a negative impact on depression.
Impaired modulation of excitatory and inhibitory neurotransmission in the brain was another potential explanation, with the authors noting gabapentin and opioids as some of the effective therapies for both conditions.
“Therefore, recognising and treating both conditions may improve the overall clinical management outcomes and patient satisfaction,” the authors suggested.
Arinze JT, Hofman A, de Roos EW, et al. The interrelationship of chronic cough and depression: a prospective population-based study. ERJ Open Res. Published online April 4, 2022. doi:10.1183/23120541.00069-2022