Hypothyroidism in Arthritis Patients Drives Up Cardiovascular Risk

LONDON – Hypothyroidism is prevalent in patients with inflammatory arthritis and is associated with increased cardiovascular risk, according to the findings of a large, primary care practice study.

The prevalence of hypothyroidism in Dutch women with inflammatory arthritis (IA) was 6.5% vs. 3.9% (P less than .0005) for those without. Corresponding figures in Dutch men were 2.4% and 0.8%, respectively (P less than .0005), according to results presented at the annual European Congress of Rheumatology.

Hypothyroidism and IA were each found to independently increase the risk of cardiovascular disease (CVD) in women, compared with women who had neither disease. Women with both conditions had more than three times the risk for CVD, compared with controls.

The findings highlight the need for primary care providers to be aware of the link between hypothyroidism and IA, suggested Dr. Hennie Raterman of the Free University Medical Center in Amsterdam.

"In inflammatory arthritis patients, you see a high coexistence of cardiovascular risk factors and cardiovascular diseases such as acute myocardial infarction and stroke," Dr. Raterman said in an interview. "On top of that, and if you have the coexistence of the two autoimmune diseases [IA and hypothyroidism], the risk is further amplified."

General practitioners act as the gatekeepers to specialist health care services in the Netherlands, and are therefore well placed to provide information about the prevalence of comorbid disease, Dr. Raterman observed.

The cross-sectional study involved the examination of electronic medical records from approximately 175,000 patients who were seen at 96 general practice clinics in the Netherlands up until 2006. IA was identified in 1,518 patients; this included patients with a diagnosis of rheumatoid arthritis, psoriatic arthritis, and ankylosing spondyloarthritis.

The overall prevalence of hypothyroidism was 5% (n = 76/1,518) in patients with IA vs. 2.3% (n = 4,153/173,543) in those without IA in the general practice population (P less than .0005).

As hypothyroidism was found to be most prevalent in women with IA, and the number of men (n = 13) included in the sample with IA was too low to achieve statistical power, the second part of the study focused on CVD risk in female patients only.

After adjustment for age and the presence of diabetes, hypertension and hypercholesterolemia, the odds ratios for the development of CVD relative to controls was 1.19 for women with hypothyroidism, 1.48 for those with IA, and 3.72 for those with both autoimmune diseases.

In the treatment of patients with comorbid IA and hypothyroidism, Dr. Raterman said that it was important to keep both conditions well controlled.

Diabetes is another autoimmune condition that may cluster in patients with IA and hypothyroidism, so paying attention to that disease may also prove important. Perhaps treating one autoimmune disease will improve the outcome of other comorbid conditions, he suggested.

Dr. Raterman and colleagues recently demonstrated that the use of anti–tumor necrosis factor-alpha therapy in patients with rheumatoid arthritis and hypothyroidism can improve thyroid function (J. Rheumatol. 2011;38:247-51).

Keeping the arthritis and the thyroid disease well controlled may be enough to address the already high risk for CVD in patients with one or the other, or both autoimmune diseases, but "when that’s not enough I think you have to target all the cardiovascular risk factors."

Dr. Raterman reported that he had no relevant conflicts of interest.

LONDON – Hypothyroidism is prevalent in patients with inflammatory arthritis and is associated with increased cardiovascular risk, according to the findings of a large, primary care practice study.

The prevalence of hypothyroidism in Dutch women with inflammatory arthritis (IA) was 6.5% vs. 3.9% (P less than .0005) for those without. Corresponding figures in Dutch men were 2.4% and 0.8%, respectively (P less than .0005), according to results presented at the annual European Congress of Rheumatology.

Hypothyroidism and IA were each found to independently increase the risk of cardiovascular disease (CVD) in women, compared with women who had neither disease. Women with both conditions had more than three times the risk for CVD, compared with controls.

The findings highlight the need for primary care providers to be aware of the link between hypothyroidism and IA, suggested Dr. Hennie Raterman of the Free University Medical Center in Amsterdam.

"In inflammatory arthritis patients, you see a high coexistence of cardiovascular risk factors and cardiovascular diseases such as acute myocardial infarction and stroke," Dr. Raterman said in an interview. "On top of that, and if you have the coexistence of the two autoimmune diseases [IA and hypothyroidism], the risk is further amplified."

General practitioners act as the gatekeepers to specialist health care services in the Netherlands, and are therefore well placed to provide information about the prevalence of comorbid disease, Dr. Raterman observed.

The cross-sectional study involved the examination of electronic medical records from approximately 175,000 patients who were seen at 96 general practice clinics in the Netherlands up until 2006. IA was identified in 1,518 patients; this included patients with a diagnosis of rheumatoid arthritis, psoriatic arthritis, and ankylosing spondyloarthritis.

The overall prevalence of hypothyroidism was 5% (n = 76/1,518) in patients with IA vs. 2.3% (n = 4,153/173,543) in those without IA in the general practice population (P less than .0005).

As hypothyroidism was found to be most prevalent in women with IA, and the number of men (n = 13) included in the sample with IA was too low to achieve statistical power, the second part of the study focused on CVD risk in female patients only.

After adjustment for age and the presence of diabetes, hypertension and hypercholesterolemia, the odds ratios for the development of CVD relative to controls was 1.19 for women with hypothyroidism, 1.48 for those with IA, and 3.72 for those with both autoimmune diseases.

In the treatment of patients with comorbid IA and hypothyroidism, Dr. Raterman said that it was important to keep both conditions well controlled.

Diabetes is another autoimmune condition that may cluster in patients with IA and hypothyroidism, so paying attention to that disease may also prove important. Perhaps treating one autoimmune disease will improve the outcome of other comorbid conditions, he suggested.

Dr. Raterman and colleagues recently demonstrated that the use of anti–tumor necrosis factor-alpha therapy in patients with rheumatoid arthritis and hypothyroidism can improve thyroid function (J. Rheumatol. 2011;38:247-51).

Keeping the arthritis and the thyroid disease well controlled may be enough to address the already high risk for CVD in patients with one or the other, or both autoimmune diseases, but "when that’s not enough I think you have to target all the cardiovascular risk factors."

Dr. Raterman reported that he had no relevant conflicts of interest.

LONDON – Hypothyroidism is prevalent in patients with inflammatory arthritis and is associated with increased cardiovascular risk, according to the findings of a large, primary care practice study.

The prevalence of hypothyroidism in Dutch women with inflammatory arthritis (IA) was 6.5% vs. 3.9% (P less than .0005) for those without. Corresponding figures in Dutch men were 2.4% and 0.8%, respectively (P less than .0005), according to results presented at the annual European Congress of Rheumatology.

Hypothyroidism and IA were each found to independently increase the risk of cardiovascular disease (CVD) in women, compared with women who had neither disease. Women with both conditions had more than three times the risk for CVD, compared with controls.

The findings highlight the need for primary care providers to be aware of the link between hypothyroidism and IA, suggested Dr. Hennie Raterman of the Free University Medical Center in Amsterdam.

"In inflammatory arthritis patients, you see a high coexistence of cardiovascular risk factors and cardiovascular diseases such as acute myocardial infarction and stroke," Dr. Raterman said in an interview. "On top of that, and if you have the coexistence of the two autoimmune diseases [IA and hypothyroidism], the risk is further amplified."

General practitioners act as the gatekeepers to specialist health care services in the Netherlands, and are therefore well placed to provide information about the prevalence of comorbid disease, Dr. Raterman observed.

The cross-sectional study involved the examination of electronic medical records from approximately 175,000 patients who were seen at 96 general practice clinics in the Netherlands up until 2006. IA was identified in 1,518 patients; this included patients with a diagnosis of rheumatoid arthritis, psoriatic arthritis, and ankylosing spondyloarthritis.

The overall prevalence of hypothyroidism was 5% (n = 76/1,518) in patients with IA vs. 2.3% (n = 4,153/173,543) in those without IA in the general practice population (P less than .0005).

As hypothyroidism was found to be most prevalent in women with IA, and the number of men (n = 13) included in the sample with IA was too low to achieve statistical power, the second part of the study focused on CVD risk in female patients only.

After adjustment for age and the presence of diabetes, hypertension and hypercholesterolemia, the odds ratios for the development of CVD relative to controls was 1.19 for women with hypothyroidism, 1.48 for those with IA, and 3.72 for those with both autoimmune diseases.

In the treatment of patients with comorbid IA and hypothyroidism, Dr. Raterman said that it was important to keep both conditions well controlled.

Diabetes is another autoimmune condition that may cluster in patients with IA and hypothyroidism, so paying attention to that disease may also prove important. Perhaps treating one autoimmune disease will improve the outcome of other comorbid conditions, he suggested.

Dr. Raterman and colleagues recently demonstrated that the use of anti–tumor necrosis factor-alpha therapy in patients with rheumatoid arthritis and hypothyroidism can improve thyroid function (J. Rheumatol. 2011;38:247-51).

Keeping the arthritis and the thyroid disease well controlled may be enough to address the already high risk for CVD in patients with one or the other, or both autoimmune diseases, but "when that’s not enough I think you have to target all the cardiovascular risk factors."

Dr. Raterman reported that he had no relevant conflicts of interest.