Ryota Shinomiya

Background: Type 2 diabetes mellitus (T2DM) is associated with impaired skeletal muscle mass and function; however, respiratory muscle involvement has not been fully investigated, particularly in Japanese patients. This study aimed to evaluate respiratory muscle strength and identify its associated factors in Japanese patients with T2DM. Methods: This cross-sectional study included 55 patients with T2DM without respiratory disease. Maximal inspiratory pressure (PImax) and maximal expiratory pressure (PEmax) were measured and expressed as percentages of the predicted values (PImax %pred and PEmax %pred). Clinical variables, including age, sex, body mass index (BMI), diabetic polyneuropathy (DPN), skeletal muscle index (SMI), handgrip strength, and 6-min walk distance (6MWD), were assessed. Correlation and multiple regression analyses were performed to identify factors associated with PImax %pred. Results: PImax %pred was significantly lower than the predicted value (69.5% [95% CI: 63.1–75.9], p < 0.001), whereas PEmax %pred did not differ significantly from the predicted value (95.6% [95% CI: 86.8–104.3]). PImax %pred was significantly associated with age, BMI, SMI, handgrip strength, and 6MWD. In multiple regression analysis, age, sex, BMI, and handgrip strength were independently associated with PImax %pred, whereas DPN was not. These findings remained unchanged after adjusting for smoking habits. Conclusions: Inspiratory muscle strength was selectively reduced in Japanese patients with T2DM and was independently associated with general physical characteristics and overall muscle strength. Inspiratory muscle weakness may reflect generalized skeletal muscle dysfunction rather than solely a neuropathic impairment. This assessment of respiratory muscle strength may provide additional insights into the physical function of patients with T2DM.

Type 2 diabetes mellitus (T2DM) is associated with reduced lower limb muscle strength and is closely linked to physical frailty. Frail individuals often face difficulty in engaging in independent exercises, making outpatient rehabilitation (OR) under Japan’s long-term care insurance system a potentially effective intervention. Therefore, in this case, we provided long-term, continued exercise support through OR to an older, frail patient with T2DM. To ensure exercise adherence and prevent acute diabetic complications, we implemented a moderate- or lower-intensity exercise program consisting primarily of aerobic and resistance training, performed twice a week for 80 min per session, over 2 years. Consequently, the knee extension force improved over time. By month 9, the patient had transitioned from frailty to robustness according to the Japanese version of the Cardiovascular Health Study criteria. Regarding glycemic control, hemoglobin A1c (HbA1c) levels remained below baseline throughout the 2-year intervention. Although a temporary increase in HbA1c was observed at month 9, switching from self-monitoring of blood glucose to intermittently scanned continuous glucose monitoring enhanced the patient’s awareness of glycemic fluctuations. Consequently, HbA1c levels were lower in the second year than in the first year. These findings suggest that long-term OR may be beneficial for improving lower limb muscle strength, physical frailty, and glycemic control in older patients with T2DM.

Proliferative diabetic retinopathy (PDR) and peripheral arterial disease (PAD) of the lower extremities are serious complications of type 2 diabetes mellitus (T2DM). Aerobic exercise has been shown to be primarily effective for glycemic control and gait disturbance owing to PAD. However, the safety and efficacy of exercise therapy in patients with PDR remain unclear. The purpose of this case report was to demonstrate the short-term effects of static stretching (SS) and daily walking over 10,000 steps on patients with T2DM presenting with PDR and PAD. The intervention consisted of 40 minutes of other-movement SS and in-hospital walking during a two-week hospitalization phase and 20-30 minutes of automatic SS and outdoor walking during a two-week home phase post-discharge. The walking conditions consisted of 10,000 steps/day, and the rate of perceived exertion was 11-12 on the Borg scale. Outcomes included the presence of a new intraocular hemorrhage and changes in intraocular pressure (IOP), blood pressure, fasting blood glucose level, biochemical parameters, cardio-ankle vascular index (CAVI), and ankle-brachial index. No new intraocular hemorrhage or increased IOP was observed during the intervention period, and blood pressure, glycemic control, and CAVI parameters improved. The results of the intervention in this case suggest that the combination of SS and walking exercises may be safe and effective.