How does osteoarthritis differ between men and women regarding prevalence, affected joints, symptoms, progression, and therapy?

Sex and Gender Differences in Osteoarthritis

Women have a 60% higher overall prevalence of osteoarthritis compared to men, with this disparity becoming most pronounced after age 40, and they experience greater pain severity, functional limitations, and disease burden despite similar radiographic findings. 1, 2

Prevalence Patterns

Overall Prevalence

• Women account for approximately 60% of all people with osteoarthritis globally, with the sex difference becoming dramatically more pronounced after age 40 years 1
• Female sex increases overall OA risk with a relative risk of 1.23 (95% CI 1.11-1.34) for prevalence compared to men 3, 4
• Among individuals aged 65 years and older, prevalence reaches approximately 60% in men versus 70% in women 5

Joint-Specific Differences

Knee Osteoarthritis:

• Women demonstrate consistently higher prevalence of knee OA across multiple disease definitions (radiographic, symptomatic, and clinical) 6
• The female predominance in knee OA is consistent across all measurement methods 6
• Knee OA is definitively female-predominant, representing a key distinguishing feature from hip OA 3

Hip Osteoarthritis:

• Hip OA shows a complex sex-dependent pattern that varies by age and disease definition 3, 6
• Radiographically defined hip OA is actually more common in males, particularly at younger ages 3, 6
• However, symptomatically or clinically defined hip OA is more common in females despite less severe radiographic changes 6
• Hip OA transitions from male predominance at younger ages to female predominance in older age groups 3

Hand Osteoarthritis:

• Women have dramatically lower incidence before age 40 but substantially higher incidence after this age compared to men 3, 4
• The incidence increases dramatically in women after age 40, with a relative risk of 1.54 (95% CI 0.83 to 2.86) for incidence 3
• This age-related shift strongly suggests hormonal influences, particularly related to menopause 3

Risk Factor Differences

Anatomical and Biomechanical Factors

• Women have distinct joint anatomy, alignment patterns, and generally lower muscle strength compared to men, contributing to differential OA risk 1
• These structural differences may explain why certain joints (particularly knees) are more vulnerable in women 1

Hormonal Influences

• The dramatic increase in female hand OA incidence after age 40 suggests estrogen reduction due to menopause plays a role 3
• However, hormone replacement therapy (HRT) studies have not shown consistent protective effects against HOA, though these observational studies may be confounded by factors such as increased bone density 3

Obesity

• Obesity represents an important risk factor for knee OA in both sexes, but is only a modest risk factor for hip OA 3
• The differential impact of obesity across joint sites may partially explain sex-specific prevalence patterns 3

Occupational Exposures

• Men: Strong evidence exists for increased hip OA risk from lifting, vibration, and cumulative physical load 3
• Men: Strong evidence shows kneeling, squatting, bending, and heavy physical demands increase knee OA risk 3
• Women: Strong evidence demonstrates kneeling, squatting, bending, and heavy physical demands increase knee OA risk 3
• Women: Strong evidence shows no increased knee OA risk from climbing stairs or ladders 3, 7
• Occupational risk factors become clinically relevant in the 40-65 year age group, with OA manifesting in the 65+ age group after cumulative exposure 4

Symptom Severity and Clinical Presentation

Pain Perception

• At identical radiographic severity levels, women report significantly greater pain severity than men 1, 8
• Women demonstrate biologically distinct pain pathways and differential activation of central pain processing mechanisms 1
• Differences in pain sensitivity, perception, reporting styles, and coping strategies contribute to this disparity 1

Functional Limitations

• Women experience greater limitations in physical function and performance compared to men, independent of BMI, OA severity, injury history, and weekly exercise levels 1, 8
• Women demonstrate higher levels of physical difficulty and disability related to OA 8

Clinical Inflammation

• Women show higher levels of clinical pain and inflammation compared to men at similar disease stages 8
• Women have decreased cartilage volume compared to men 8

Treatment and Healthcare Utilization Differences

Medication Use

• Women utilize analgesic medications more frequently than men for OA management 1
• Despite higher medication use, women continue to report worse pain outcomes 1

Surgical Interventions

• Women undergo arthroplasty procedures less frequently than men despite higher symptom burden 1
• Women demonstrate poorer prognosis and outcomes after surgical interventions compared to men 1

Healthcare Access

• Women use more healthcare services overall for OA management compared to men 8
• This increased utilization occurs despite potentially receiving less definitive surgical treatment 1, 8

Disease Progression Considerations

Age-Related Patterns

• OA rarely develops before age 40 in either sex, but incidence increases dramatically after this threshold 3, 4
• The age of 40 years serves as a diagnostic cut-off with a likelihood ratio of 3.73 (95% CI 2.69 to 5.18) 3
• Women's risk acceleration after age 40 is more pronounced than men's, particularly for hand and knee OA 3, 4

Joint-Specific Morphometry

• Women have smaller joint parameters and dimensions across multiple joint sites compared to men 8
• These anatomical differences may contribute to differential biomechanical stress patterns 8

Clinical Implications

The recognition of these sex differences should guide clinical assessment and treatment planning, with particular attention to:

• Higher index of suspicion for knee and hand OA in women over age 40 3, 1
• Understanding that women's pain reports at lower radiographic severity levels represent genuine biological differences, not over-reporting 1
• Recognizing that hip OA in women may be symptomatic despite less severe radiographic findings 6
• Considering that women may require more aggressive pain management strategies despite similar structural disease 1
• Accounting for occupational exposures differently by sex when assessing risk, particularly for hip versus knee involvement 3