Epidemiology is the study of health and disease patterns.  What causes a specific disease?  How does it spread?  How many people are newly diagnosed in a year?  How many people are managing the disease on an ongoing basis?

Two of the statistics that epidemiologists give us are incidence and prevalence.  This topic would bore me to tears if I had to produce these statistics for a living, but when I’m researching a disease, these are numbers that I want to know.  Incidence  tells us about how many new diagnoses are made per year (or, more technically, per any given time period).  Prevalence  tells us how many people are being treated on an ongoing basis during that same time period.

Incidence – In studying rheumatoid arthritis, epidemiologists have learned that for every 100,000 adults, there are an average of 41 new cases of RA diagnosed annually.  The number of people newly diagnosed increases with age:  8.7 per 100,000 for ages 16-34, versus 54 per 100,000 for people over age 80.

Prevalence – For every 100,000 adults, there are 500-920 people dealing with RA on an ongoing basis (statistics vary depending on which diagnostic criteria are used, which country is being considered, and a few other variables).

The incidence and prevalence of other types of autoimmune arthritis varies widely1:

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As you can see, the data on PsA is sub-optimal.  AS is twice as common as RA, yet isn’t nearly as well-known.  MCTD and AOSD have such a low prevalence that they are considered rare diseases by the Office of Rare Diseases of the National Institute of Health, and by Orphanet.  JIA is also listed in the rare diseases database.

Age – Age of onset varies considerably depending on the type of arthritis.  By definition, disease onset before age 16 means that it’s a subtype of Juvenile Idiopathic Arthritis.  Children who receive a diagnosis of one of the subtypes of JIA do not receive a different diagnosis as they age; the diagnosis remains JIA, even if the person lives to be 80 years old.

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These are averages, not rules.  Immune systems don’t read textbooks, thus don’t know when the books say they might malfunction.

1Statistics on the incidence and prevalence of Sjogren’s Syndrome and UCTD are difficult to find.


Keeping My Thoughts To Myself

We’ve all heard that old joke, “Doctor, it hurts when I do this…”  The doctor responds, “Then don’t do that!”

We laugh, but I’d sure like to see that thought process expanded.  If a medicine is thought to cause adverse effects, why is the solution to add another medicine in hopes of controlling those adverse effects?

Off to the pharmacy I go:

Three weeks later:

Slacktivism Is Not Enough

Imagine that your doctor refers you to a specialist.  It takes months to get an appointment, but eventually the specialist gives a diagnosis:  You have a highly inflammatory disease which often leads to joint destruction, deformity and loss of function.  Chronic pain, disability and excess mortality are unfortunate sequelae.” (cf)

Stunned, you share your diagnosis with a few friends and coworkers.  Obviously misunderstanding, one shrugs, “Oh, I have that in my little finger.”  Another replies, “Just take an Aleve.”  As you struggle with your new regimen of doctor’s appointments and prescriptions medicines, people impatiently demand, “Aren’t you better yet?”


As someone who never changes my Facebook photo and ignores all gimmicky “post this to raise awareness…” pleas, last week I found myself in the interesting position of promoting IAAM’s FB Post Your Numbers awareness campaign.

Post Your Numbers was designed to spread the word that osteoarthritis is very different from rheumatoid arthritis – both in how it’s caused and in who is affected.

Doctor Grumpy graciously posted a public service announcement to help spread the word about our FB awareness campaign.  His readers jumped in saying that awareness isn’t enough and asked how people can really help.  They wanted facts, and they want to know what they can do.


Fact:  There are over 100 types of arthritis.  They are different.

Fact:  Of those 100+ arthritic diseases, seven of them are considered autoimmune arthritis.  The person’s immune system kicks into overdrive and instead of simply attacking foreign invaders like it is supposed to, it attacks its body’s own tissues.

Fact:  Autoimmune Arthritis is often treated with chemotherapy drugs.

Fact:  Autoimmune Arthritis isn’t limited to pain in one or two joints.  These are systemic diseases.  In addition to multiple joints, tendons and ligaments are affected.  Organs can be destroyed.  Some people lose their eyesight due to autoimmune arthritis.  Others lose their hearing.  The skin can be affected.  Lung disease can be caused by autoimmune arthritis, as can heart disease.

Fact:  Autoimmune Arthritis can strike at any age.  It is not “an old person’s disease.”

Fact:  Autoimmune Arthritis symptoms can lessen and flare without warning.  A person can feel fine in the morning, but be unable to walk a few hours later.

Fact:  A great amount of overlap exists among these diseases, and sometimes doctors have trouble telling which form a patient is afflicted with.   Patients are sometimes told, “It doesn’t matter which one of these diseases you have, because they’re treated the same way.”

Fact: There is no cure.

To Learn More:

Rheumatoid Arthritis affects multiple joints symmetrically.  Typically both sides of the body are affected:  both wrists, both hands, both ankles, both feet…  There are many links in my sidebar leading to information about RA.

Psoriatic Arthritis is very similar to rheumatoid arthritis, with the addition of the skin involvement of psoriasis.

Ankylosing Spondylitis is marked by bones of the spine fusing to one another (from the disease, not due to a surgical procedure).  As noted by one of Doctor Grumpy’s commenters, there are forms of spondylitis that don’t qualify as AS.  It is my personal opinion that diagnostic criteria will eventually change and that these diseases will eventually be diagnosed and treated soon enough that fusion can be prevented.

Systemic Lupus Erythematosis is probably the best known of these diseases.  Fifty years ago, a teenage girl diagnosed with lupus wasn’t expected to live to 20.  That is no longer true.  Great treatment strides have been made, but there is still a long way to go.

Sjögren’s Syndrome attacks the mucous membranes and moisture-secreting glands.  Dry eyes and mouth are early symptoms.  Gritty eyes feel as if they have sand in them.  People’s mouth feels so dry that it’s difficult to talk or swallow.  This sounds innocuous, but imagine what it would be like if these symptoms never went away.

Mixed Connective Tissue Disease – sometimes called undifferentiated connective tissue disease – is the diagnosis when a person has symptoms of lupus, scleroderma and polymyositis.  RA symptoms can occur, too.  Sometimes this is called “overlap syndrome.”

Adult Still’s Disease  In addition to the joint pain that comes with all autoimmune arthritic diseases, Stills is noted for high fevers and rash.  The brief post I wrote introducing Stills is here.

Juvenile Arthritis is the diagnosis when one of these diseases occurs in a child under 16 years of age.


We need a cure.  Donate to organizations that fund research looking for a cure for the different forms of autoimmune arthritis:

Spondylitis Association of America

National Psoriasis Foundation

Lupus Foundation of America

Sjögren’s Syndrome Foundation

Arthritis Foundation