Medical Bulletin 13/ July/ 2024

Osteoarthritis Linked to Rapid Worsening of Severe Long-Term Conditions: Study

Osteoarthritis, a condition where the protective cartilage on the ends of bones deteriorates, may more than double the risk of rapid progression to multiple severe long-term conditions, known as multimorbidity, according to a 20-year study published in the open-access journal RMD Open. The study reveals four distinct speeds of progression to multimorbidity, highlighting the impact of osteoarthritis on overall health.

The research suggested that persistently low levels of physical activity, a high-calorie diet, and chronic low-grade inflammation may explain the link between osteoarthritis and the increased risk of developing other long-term conditions.

Around 70% of those with osteoarthritis are likely to have other long-term conditions, but the speed and severity of their development were previously unclear. To investigate this, researchers analyzed continuously collected healthcare data which included around 1.4 million residents. They focused on individuals aged 40 or older and were newly diagnosed with osteoarthritis between 2008 and 2009. These cases were matched with two people of the same age and sex who did not have osteoarthritis.

During the study period, 5,318 people were newly diagnosed with knee osteoarthritis, 2,479 with hip osteoarthritis, 988 with hand osteoarthritis, 714 with osteoarthritis in other joints, and 499 with generalized osteoarthritis.

Out of the total participants, 1,296 did not develop any other long-term condition, while 28,242 did. Four distinct patterns of progression emerged: mild multimorbidity late progression (class 1), mild multimorbidity early progression (class 2), moderate multimorbidity (class 3), and severe multimorbidity (class 4). Initially, the average number of long-term conditions was low (one or none) in all four classes. Those in class 1 progressed the slowest to developing multiple long-term conditions, with an average of around three conditions by the end of the tracking period. In contrast, those in class 4 progressed the fastest, accumulating an average of around ten long-term conditions.

The severity of each long-term condition was assessed using the disability weighting from the Global Burden of Disease (GBD) study. Disability levels mirrored the categorization, being lowest in class 1 and highest in class 4, where over half (57%) of participants had died by the end of the tracking period. Osteoarthritis prevalence was also lowest in class 1 (29%) and highest in class 4 (42%).

Osteoarthritis was associated with a 29% increased risk of class 1 membership but more than doubled the risk for class 4 membership. Despite this, the presence of osteoarthritis alone was a poor predictor of any class of membership. Age remains a significant factor in developing long-term conditions, but the study found that the correlation between osteoarthritis and multimorbidity extended beyond age.

The findings underscored the importance of addressing lifestyle factors such as physical activity and diet in managing osteoarthritis and preventing the rapid progression of other severe long-term conditions.

Reference: Dell’Isola, A., Recenti, F., Englund, M., & Kiadaliri, A. (2024). Twenty-year trajectories of morbidity in individuals with and without osteoarthritis. RMD Open. doi.org/10.1136/rmdopen-2024-004164

Study Links Sleep Duration to Blood Vessel Damage in Recently Diagnosed Diabetics

New research to be presented at this year’s Annual Meeting of the European Association for the Study of Diabetes (EASD) revealed that individuals recently diagnosed with type 2 diabetes (T2D) who experience either short or long sleep durations are more likely to develop microvascular disease, which can lead to severe complications. The study, conducted by Mette Johansen and Thomas Olesen from the Steno Diabetes Center Odense, Odense University Hospital, Denmark, and their colleagues, highlighted the potential impact of sleep duration on diabetes-related vascular health.

Microvascular complications, including retinopathy and nephropathy, significantly contribute to the morbidity associated with T2D. Previous studies have indicated that variations in sleep duration might influence the risk of developing these complications. This study aimed to investigate the relationship between sleep duration and the prevalence of microvascular disease in individuals newly diagnosed with T2D.

The researchers utilized data from the Specialist Supervised Individualized Multifactorial Treatment of New Clinically Diagnosed Type 2 Diabetes in General Practice (IDA) study. Participants' sleep durations were measured over a 10-day period. Sleep duration was categorized as short (<7 hours), optimal (7 to <9 hours), or long (≥9 hours). Microvascular disease was defined by either a urine albumin/creatinine ratio (UACR) ≥ 30 mg/g or the presence of diabetic retinopathy (DR) assessed through mydriatic retinal imaging or ophthalmoscopy.

The analysis included 396 participants with valid sleep duration, UACR measurements, and eye examinations. The median age of participants was 62 years, with an average diabetes duration of 3.5 years. The cohort predominantly consisted of overweight individuals, with a median BMI of 31, and 68% were on antihypertensive medication.

Among the participants, 12% had short sleep duration, 60% had optimal sleep duration, and 28% had long sleep duration. The prevalence of microvascular damage was 38% in the short sleep duration group, 18% in the optimal sleep duration group, and 31% in the long sleep duration group. Short sleep duration was associated with a 2.6 times increased risk of microvascular disease compared to optimal sleep duration, while long sleep duration was linked to a 2.3 times increased risk.

For participants under 62 years old, short sleep duration increased the risk of microvascular damage by 23% compared to optimal sleep duration. However, for those aged 62 and over, short sleep duration was linked to a 5.7 times increased risk. The effect of age on the relationship between long sleep duration and microvascular disease was not statistically significant.

The findings underscored the importance of optimal sleep duration in managing newly diagnosed T2D patients and suggested that both insufficient and excessive sleep may exacerbate the risk of microvascular complications, especially in older adults.

Reference: Mette Johansen, Thomas Olesen, et al.; Study finds short and long sleep duration associated with blood vessel damage in those recently diagnosed with type 2 diabetes; DIABETOLOGIA; MEETING: Annual Meeting of the European Association for the Study of Diabetes (EASD)

Lipidomics Shows health benefits of switching to plant-based fats

Switching from a diet high in saturated animal fats to one rich in plant-based unsaturated fats affects the fat composition in the blood, which in turn influences long-term disease risk.

A recent study published in Nature Medicine, conducted by a team of researchers from Chalmers University of Technology, Sweden, the German Institute of Human Nutrition, and several other universities, showed that it is possible to accurately measure diet-related fat changes in the blood and directly link them to the risk of developing cardiovascular disease and type 2 diabetes.

The World Health Organization (WHO) emphasizes the importance of healthy diets in preventing chronic diseases and recommends replacing saturated fats with plant-based unsaturated fats to lower the risk of heart and metabolic diseases. However, these guidelines are only moderately certain due to the limitations of past studies.

This new study overcomes these limitations by using a method called ‘lipidomics’ to closely analyze the fats in the blood. The detailed analysis helps link diet and disease in a new and effective way. The study combined controlled dietary intervention studies, where participants follow strict diets, with long-term health data from previous cohort studies.

In the study, researchers conducted a dietary intervention involving 113 participants. For 16 weeks, one group ate a diet high in saturated animal fats, while the other group followed a diet rich in unsaturated plant-based fats. Blood samples were analyzed using a method called lipidomics to identify specific lipid molecules that reflected the different diets consumed by each participant.

These results were then compared to data from large observational studies that tracked initially healthy participants over several years. The analysis showed that participants with higher levels of beneficial lipid molecules (MLS) had a significantly reduced risk of developing heart and metabolic diseases.

Additionally, the study examined whether individuals with low MLS levels, indicating a diet high in saturated fats, would benefit from a healthier diet. Using data from the PREDIMED trial, which focused on the Mediterranean diet rich in unsaturated plant fats, researchers found that diabetes prevention was most pronounced in individuals who started with low MLS levels.

“We summarized the effects on blood lipids with a multi-lipid score (MLS). A high MLS indicates a healthy blood fat profile, and a high intake of unsaturated plant fat and low intake of saturated animal fat can help achieving such positive MLS levels", says Fabian Eichelmann from the German Institute of Human Nutrition and first author of the study.

Reference: Eichelmann, F., et al. (2024). Lipidome changes due to improved dietary fat quality inform cardiometabolic risk reduction and precision nutrition. Nature Medicine. doi.org/10.1038/s41591-024-03124-1.