A major study of medical records from some 100,000 people has found links between psoriasis and other diseases, finding that people with the skin condition are more likely to develop diabetes and cardiovascular disease, among other conditions.

The research, from dermatologists at the University of Pennsylvania, and published in JAMA Dermatology, also found that the risk of other diseases got worse the more severe the psoriasis was.

The following is the full list of conditions that people with psoriasis were more likely to develop, given in order of increasing likelihood (expressed as odds ratio – OR):

  • COPD (chronic obstructive pulmonary disease), OR 1.08
  • Diabetes, OR 1.22
  • Peptic ulcer, OR 1.27
  • Kidney disease, OR 1.28
  • Diabetes with complications, OR 1.34
  • Heart attack, OR 1.34
  • Mild liver disease, OR 1.41
  • PVD (peripheral vascular disease), OR 1.38
  • Rheumatologic disease, OR 2.04

The research team is led by Joel Gelfand, associate professor of dermatology and epidemiology at the University of Pennsylvania’s Perelman School of Medicine. He gave Medical News Today his view on which of the comorbidities associated with psoriasis are most important clinically:

Based on our prior work, diabetes and cardiovascular disease seem to be the most important links – cardiovascular disease associated with psoriasis explains much of the increased mortality seen in patients with more severe psoriasis.”

There is power to the epidemiological study because of the numbers involved. It found 9,035 patients with psoriasis among the total of 99,385 records in the study. Everyone analyzed was between 25 and 64 years of age.

As well as showing the higher prevalence of the diseases in the people with psoriasis, the data also give a strong suggestion that the chance of these conditions increases with the severity of the psoriasis, giving, the authors say, clues to how the diseases are connected.

The researchers call this relationship a kind of “dose response” – from medicines, where, to a point, there is often a bigger effect as the dose increases.

Dr. Gelfand told MNT:

“The link to severity is important for several reasons.

First, it establishes a ‘dose-response,’ which suggests, but doesn’t prove, a causal relationship.

Second, the findings are clinically important as psoriasis is such a variable disease. By understanding how degree of skin affected is associated with various health risks, patients and their care givers can better understand how these study results may apply to them on an individual basis.”

As to a biological explanation about how the diseases are connected, Dr. Gelfand and his colleagues discuss their theories about this etiology – cause of disease – in the study paper.

Dr. Gelfand explained this for us: “Psoriasis, atherosclerosis and diabetes all share chronic inflammation as an underlying problem – chronic inflammation is therefore the biologic theory for why these diseases are linked but a causal relationship has not been definitively proven.”

He was also asked about the clinical relevance of the study’s findings for doctors and patients with psoriasis. Dr. Gelfand said:

“The take away point is that increasing severity of skin psoriasis is a marker that other serious medical conditions may be present.

Therefore, age appropriate, comprehensive medical care is important for patients with psoriasis, especially those who suffer from more extensive skin disease.”

Dr. Gelfand concludes:

The goals are two-fold. One, identify and treat medical illnesses. Two, institute preventative health measures to lower the risk of future health problems.”