Assessment of Modifiable and Non-Modifiable Risk Factors for Knee Osteoarthritis Over the Lifespan and Their Association with Poor Lifestyle: Comparative Study

Background: One of the main causes of injury around the world is osteoarthritis (OA) of the knee. Lifestyle factors that can be changed; like being overweight; physical inactivity, smoking, and unhealthy diet, may be very important in deterioration of knee osteoarthritis (KOA), especially when combined with risk factors that can't be modified, like age, sex, genetics, and a history of injury. Aim: Our objectives were expression of the risk factors for KOA both modifiable and non-modifiable. We also want to see how these risk factors are linked to a poor lifestyle and the prevalence of KOA among Saudi and Egyptian populations. Methods: A cross-sectional survey will be distributed throughout Saudi and Egyptian participants between November 2025 to January 2026. An online questionnaire was designed, it includes informed consent of participants, sociodemographic data, questions about knee osteoarthritis, poor lifestyle, modifiable and non-modifiable risk factors. Data was collected through online questionnaires or interviews with people. Statistical analysis was carried out using the Statistical Package for Social Sciences (SPSS Inc, Chicago, IL, USA, version 25). Results: The prevalence of KOA was nearly the same in both nations (29.6% Saudis vs. 31.5% Egyptians). Two thirds of participants from males (65%) from each nation, the average age was 35.0±0.74 (Saudis) and 44.5±2.07 (Egyptians) which was significantly different at p-value 0.001. Most of them from 20-40 years (56% Egyptians vs. 72.2% Saudis), in addition, about 22.5% who were more than 60 years-old from Egyptians vs. 8.6% Saudis. Obese participants were found among Saudis (29.6%) vs Egyptians (23.7%) at p-value = 0.010. The family history of knee pain was more among Saudis (28.6%) vs 11% of Egyptians, also, genetic joint disorder (12.5% Saudis) vs. 6.5% in Egyptians (at p-value = 0.017). The main factor to knee osteoarthritis previous knee injury and aging in Egyptians (28.7% and14.6%) vs. Saudis (7.3% and 11%) at p-value= 0.023. Egyptians were suffering from knee OA mainly at adult and old age of 31-60 years (24.8%), while Saudi participants suffered from KOA from young age at 20 years (p = 0.033). Egyptians was found to perform activities that put stress on the knees in running more than Saudis (p = 0.037), while Saudis more in weightlifting and squatting. Sedentary was found more among Saudis, while high level of physical activity such as football and running was found among Egyptians. Consuming fresh vegetables and fruits and whole grains (64.5% Egyptians vs 51.2% Saudis). On the other hand, poor lifestyle, Saudis consumed more sugars, carbohydrates, and fats (74.4%) vs Egyptians (57.7%) at p = 0.041. Conclusion: This study compared between Saudis and Egyptians in the prevalence of KOA (which not significantly different), and the modifiable and non-modifiable risk factors related to the KOA symptoms. The most effective plans to prevent KOA were some positive changes in lifestyle like encouraging physical exercises and some active duties and decreasing sedentary lifestyle. Also, controlling BMI, through healthy diets like vitamins, vegetables, fruits, and avoiding fast food, more sugars and carbohydrates. Protective policies should be applied at a young age and awareness at schools to prevent obesity in childhood. So, this study provided some respected insights for healthcare providers, physicians and consultants who are dealing with KOA in Saudi Arabia and Egypt.