PORTLAND, ORE. — Psoriasis patients face an increased risk of comorbidities ranging from depression to MI, but most don't know that.
“People don't know what you don't tell them, so please educate your patients about these risk factors,” Dr. Theresa Devere said at the annual meeting of the Pacific Dermatologic Association. “We should all be educating and screening people for comorbidities of psoriasis. At the least, perhaps make a handout that lists what they may be at risk for.”
Psoriatic Arthritis
A common comorbidity is psoriatic arthritis, which occurs in 11%–31% of patients before, concurrently, or after the onset of psoriasis, according to Dr. Devere. Telltale symptoms that warrant referral to a rheumatologist include pitting and discoloration of the nails, swollen finger joints, sausage finger or toe (dactylitis), and swollen heel at the Achilles tendon.
“Axial psoriatic arthritis can be a little more difficult to ascertain whether it's arthritis or not, but people with this condition will complain of lower back pain and hip pain,” said Dr. Devere of the department of dermatology at Oregon Health and Science University, Portland.
Depression
In a 1998 National Psoriasis Foundation survey of 17,350 people with psoriasis, 54% reported feeling depressed (Arch. Dermatol. 2001;137:280–4). An earlier study found that 81% of psoriasis patients reported that having the disease led to feelings of embarrassment and shame, 19% had experienced social rejection, and 6% of younger patients reported suicidal ideation (Br. J. Dermatol. 1998;139:846–50).
“We ask psoriasis patients to fill out a sheet that asks them if they've been feeling sad for the past couple of weeks and if they've had any suicidal ideation,” Dr. Devere said. “It's almost easier to get them to say yes or no on paper rather than asking them outright.”
Another study found that successful treatment of psoriasis with PUVA reduced disability and stress related to psoriasis, but did not impact anxiety, depression, and worrying (Br. J. Dermatol. 2004;151:1219–26). “Treatment of psoriasis may or may not improve depression and anxiety,” she said. “Screening and referral to a mental health professional may be helpful.”
Smoking
The Nurses' Health Study II, which followed more than 78,000 women over 14 years, found that current smokers were at higher risk for developing psoriasis, compared with past smokers (risk ratios of 1.87 and 1.37, respectively). It concluded that the risk of psoriasis increased with duration, intensity, and pack-years of smoking (Am. J. Med. 2007;120:953–9).
Another study found that patients who smoked more than 20 cigarettes per day had a twofold increased risk of clinical severe psoriasis, compared with those who smoked 10 or fewer cigarettes per day; the association was stronger among women (Arch. Dermatol. 2005;141:1580–4).
“Why does this happen? Nicotinic cholinergic receptors have been demonstrated on keratinocytes, which may control keratinocyte adhesion and upward migration in the epidermis,” Dr. Devere said. “Nicotine also alters immune responses by directly interacting with T cells and dendritic cells.”
She added that smoking induces “an overproduction of inflammatory cytokines, which may be associated with psoriasis severity.”
Alcohol Intake
Large cohort studies have showed a higher incidence of alcoholism in psoriasis patients. One reported that 17%–30% of patients with moderate to severe psoriasis have problems with alcohol (Br. J. Dermatol. 2008;158:138–40). Another study suggested that alcohol use is associated with decreased response to treatment in men (J. Am. Acad. Dermatol. 1993;28:730–2). “I have three male alcoholic patients that I cannot get better on any drug,” she said.
Obesity
One large, case-control study found that the risk of psoriasis had a 1.6 odds ratio for individuals with a body mass index of 25–30 kg/m
Other studies have found that leptin levels are increased in obesity and in the serum and tissue of severe psoriatic patients, and that leptin increases T-cell proliferation and stimulates TNF alpha production, which may link psoriasis and obesity, she said.
Dr. Devere also noted two case reports of psoriasis remission after gastric bypass surgery (Obes. Surg. 2004;14:1132–4; 2006;16:94–7). “Both patients had severe psoriasis for 15 and 39 years, respectively, without remission on multiple treatments,” she said. “After gastric bypass surgery and significant weight loss, both patients had complete remission of their psoriasis.”
Atherosclerotic Conditions
Psoriasis has also been shown to heighten the risk of a full range of atherosclerotic conditions.
A recent Veteran Affairs study showed that overall mortality (OR 1.86) and the following vascular diseases were significantly increased among patients with psoriasis: ischemic heart disease (OR 1.78), cerebrovascular disease (OR 1.70), and peripheral vascular disease (OR 1.98) (Arch. Dermatol. 2009;145:700–3). “Patients with psoriasis should be encouraged to identify and manage their modifiable cardiovascular risk factors,” Dr. Devere said.