5 minute read
psoriasis is a common chronic skin problem where dry, red patches on different areas of your body can develop at any age. these areas can be painful, itchy and cause joint stiffness and swelling, according to the canadian dermatology association , disrupting sleep, mobility and daily activities.
in fact, an estimated one million canadians live with psoriasis and its negative effects of physical pain and discomfort, as well as an increased risk of depression and anxiety. the association reports that a national survey of 500 people found that one-third of respondents saw their psoriasis or related condition as a significant barrier in their day-to-day life. having psoriasis can also lead to arthritis in as many as 30 per cent of patients and other chronic diseases, including heart attack and stroke , cancer , diabetes and liver disease.
healthing spoke with dr. melinda gooderham, dermatologist, clinical researcher and medical director of the skin centre for dermatology in peterborough, ont. she specializes in inflammatory diseases of the skin like psoriasis.
dr. gooderham: psoriasis is a dysfunction of the immune system that causes inflammation in the body. one of the ways that inflammation develops is by the chemical messengers that tell the skin to grow faster. typically, a skin cell has a lifespan of about 30 days. in psoriasis, it’s about five days. when your skin cell grows through its 30-day cycle, it comes to the surface and flakes off. but in psoriasis, the skin cell is too immature to fall off so it holds onto its neighbour and builds these thick plaques and thick scales. it also causes more blood flow and growth of blood vessels in the area, which makes it more red.
advertisement
dr. g.: dry, scaly plaques on your elbows, your knees, your scalp — those are the more common places. the colour can vary based on skin colour, so in lighter-pigmented individuals, the skin would look red, while in darker, more pigmented skin, it often looks more violet. [the affected area] is very well demarcated, like you could almost draw a line around it with a pencil. psoriasis can also develop in more sensitive areas, in the groin, on the genitals, under the breasts, in the underarms, and it looks a bit different there because those areas are more moist. they look like little lesions in the body folds. people sometimes think they have a yeast infection, so it’s important to get those hidden areas assessed.
dr. g.: you inherit a genetic predisposition. we know it’s related in families. a lot of people will say, ‘my parents don’t have it,’ but it’s not quite like that. you inherit the gene that could turn it on, although it’s not always turned on. so what can turn it on? sometimes it’s triggered by an infection or a new medication, like a beta blocker for heart disease or lithium which is used for certain mental health disorders. it is proven that psoriasis certainly flares up with stress, but we don’t want people thinking, ‘oh, if i get stressed i’m going to get psoriasis.’ it’s not like that. you have to be predisposed to psoriasis and then some trigger turns on that immune response.
advertisement
dr. g.: we know that patients who smoke and drink alcohol can have worse psoriasis, so we try to encourage a healthy lifestyle, quitting smoking and reducing alcohol. and we know psoriasis can be worse with obesity, so weight management is one of the recommendations for some patients. it’s also been well-documented that in patients who’ve had gastric bypass and lost a lot of weight, their psoriasis is reduced. so there’s a link to weight, alcohol and smoking, that those will make it worse, not that they caused it. what’s happening is ongoing systemic inflammation in the body, not just in the skin. so anything that’s going to contribute to or aggravate the inflammation, can make it worse. with that systemic inflammation, you can get things like heart disease and diabetes — things that we see at a higher rate in psoriasis patients. the higher the risk, the more severe your psoriasis is, likely perpetuating or feeding into that inflammatory cascade.
dr. g.: we typically uses the terms mild, moderate and severe, based on the body surface area. so your hand print, including your fingers, is one per cent of your body surface area. if your whole knee is involved, that might be the equivalent of one handprint. so two knees of psoriasis would be two per cent. anything up to three per cent would be considered mild, where the systemic inflammation is less and you would easily use a prescription topical cream because we’re not so worried about inflammation through the whole body. some people have 50 per cent of their body covered in psoriasis, so we need to treat the systemic inflammation. for moderate to severe, we would go to pills, injections or phototherapy which can be used in all severities. you basically stand in a photo booth with a special light that shines on you. [the number and length of phototherapy sessions depends on the individual.]
advertisement
one in three patients with psoriasis can have that inflammation in their joints, psoriatic arthritis , which can cause pain and disability. we’ll treat patients who didn’t even know they had arthritis, but all of a sudden they feel like they can run a marathon because they feel so good. arthritis can be so gradual. i had one patient tell me, ‘i get up every morning and i run down the stairs and have my coffee, not because i’m in a hurry, but because i can. i haven’t done it in years.’
dr. g.: there are a couple main things. first, psoriasis is not contagious. we’re always trying to teach that because when people see someone with psoriasis, they might shy away from them. secondly, there’s no cure, but we can manage it and we can get people clear or almost clear so that they can live a normal life.
for more information about psoriasis, visit the canadian dermatology association .
