Decline of the lung function and quality of glycemic control in type 2 diabetes mellitus

Impaired muscle oxygenation despite normal pulmonary function in type 2 diabetes without complications

Long-term hyperglycemia in individuals with type 2 diabetes (T2D) can detrimentally impact pulmonary function and muscle oxygenation. As a result, these factors can impede the body's adaptation to physical exertion. We aimed to evaluate the oxygen pathway during maximal exercise among overweight/obese individuals with type 2 diabetes free from complications, in comparison with a group of matched overweight/obese individuals without diabetes, specifically concentrating on the effects on pulmonary function and muscle oxygenation. Fifteen overweight/obese adults with type 2 diabetes [glycated hemoglobin (HbA1c) = 8.3 ± 1.2%] and 15 matched overweight/obese adults without diabetes underwent pre- and post exercise lung function assessment. A maximal incremental exercise test was conducted, monitoring muscle oxygenation using near-infrared spectroscopy and collecting arterial blood gas samples. Both groups exhibited normal lung volumes at rest and after exercise. Spirometric lung function did not significantly differ pre- and post exercise in either group. During maximal exercise, the type 2 diabetes group showed significantly lower augmentation in total hemoglobin and deoxygenated hemoglobin compared with the control group. Despite comparable usual physical activity levels and comparable heart rates at exhaustion, the type 2 diabetes group had a lower peak oxygen consumption than controls. No significant differences were found in arterial blood gas analyses ([Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text]) between the groups. Individuals with type 2 diabetes free from complications displayed normal pulmonary function at rest and post exercise. However, impaired skeletal muscle oxygenation during exercise, resulting from reduced limb blood volume and altered muscle deoxygenation, may contribute to the lower V̇o2peak observed in this population.NEW & NOTEWORTHY Individuals with type 2 diabetes free from micro- and macrovascular complications have normal resting pulmonary function, but their V̇o2peak is impaired due to poor skeletal muscle oxygenation during exercise. Tailoring exercise regimes for this population should prioritize interventions aimed at enhancing muscle oxygenation and blood flow improvement.

Pulmonary Pathology Among Patients with Type 2 Diabetes Mellitus: An Updated Systematic Review and Meta-analysis

BACKGROUND

Restrictive lung pathology was reported in the previous meta-analysis among patients with Type 2 Diabetes mellitus (T2DM) which is date back to 2010.

OBJECTIVE

To see the effect of T2DM on pulmonary functions through updated systematic review and meta-analysis.

DATA SOURCE

PubMed.

STUDY ELIGIBILITY CRITERIA

English language case-control or cross-sectional studies, published between 1 January 2010 to 31 August 2018.

PARTICIPANTS AND INTERVENTION

T2DM and non-diabetic subjects were compared for at least one of the pulmonary function variables i.e. Forced expiratory volume in 1st second (FEV1), % FEV1, Forced vital capacity (FVC), % FVC and % FEV1/FVC.

STUDY APPRAISAL AND SYNTHESIS METHODS

Methodological quality of the study was assessed using Newcastle-Ottawa Quality Assessment Scale. Meta-analysis was done using Review Manager 5.3 (RevMan 5.3) and meta-regression was conducted using R statistical software.

RESULTS

We selected 22 articles that met our inclusion and exclusion criteria. Results reveal that among patients with T2DM all variables were reduced except %FEV1/FVC which shows statistically nonsignificant results with P=0.46. This confirms that T2DM patients have a restrictive type of lung pathology.

LIMITATION

Only articles from the PubMed database were included. Conclusion and Implications of Key Findings: This review affirms the existing evidence of restrictive pathology among patients with T2DM. The future study could be conducted to see the effect of various rehabilitation protocols on pulmonary function among patients with T2DM.

Diabetic lung, an underrated complication from restrictive functional pattern to pulmonary hypertension

In patients with type 1 and type 2 diabetes mellitus (DM), respiratory function abnormalities have been reported with regard to lung volumes, pulmonary diffusing capacity, control of ventilation, bronchomotor tone, and neuroadrenergic bronchial innervation. Indeed, the decrease in lung volumes and the impairment of diffusing capacity might have important clinical implications. Furthermore, there is an increasing evidence of a link between DM and pulmonary hypertension (PH) related to an involvement of the pulmonary vascular structures. These findings support the view of the lung as target organ in DM. In this paper, we briefly describe the main derangements of the respiratory system in DM and the inherent mechanisms.

The effects of type 2 diabetes mellitus and its complications on physical and pulmonary functions: A case-control study

AIMS

This study was planned to determine the effects of type 2 diabetes mellitus (DM) and its complications on physical and pulmonary functions. Methods: A total of 110 individuals aged 40-65 years were included in the study, 58 with type 2 DM (study group) and 52 without DM (control group). Physical activity level, functional capacity, pulmonary function, and comorbidity levels were compared between the groups. Results: The mean age of the individuals was 52.42 ± 5.88 years. Six-minute walk test distance was 507.2 ± 51.70 m in the study group and 532.23 ± 50.32 m in the control group (p < 0.05, Cohen's d = 0.49). The pulmonary function test results of the study and control groups were determined as forced vital capacity (FVC) (%): 99.17 ± 14.13 and 104.65 ± 16.01 (p > 0.05), forced expiratory volume in one second (FEV1) (%): 96.78 ± 14.43 and 99.73 ± 15.80 (p > 0.05), and FEV1/FVC ratio: 81.97 ± 4.62 and 80.16 ± 5.27 (p > 0.05), respectively. The Charlson Comorbidity Index scores of the study and control groups were 1.83 ± 0.82 and 0.12 ± 0.32 (p < 0.05). Conclusions: Type 2 DM was associated with lower functional capacity and higher rates of comorbid diseases. Therefore, potential causes of these parameters should be considered in the rehabilitation of type 2 diabetic patients.

The Influence of Clinically Diagnosed Neuropathy on Respiratory Muscle Strength in Type 2 Diabetes Mellitus

OBJECTIVES

This cross-sectional study investigated the influence of clinically diagnosed neuropathy (cdNP) on respiratory muscle strength in patients with type 2 diabetes mellitus (T2DM).

METHODS

110 T2DM patients and 35 nondiabetic healthy controls (≥60 years) were allocated to one of three groups depending on the presence of cdNP: T2DM without cdNP (D-; n = 28), T2DM with cdNP (D+; n = 82), and controls without cdNP (C; n = 35). Clinical neurological diagnostic examination consisted of Vibration Perception Threshold and Diabetic Neuropathy Symptom score. Respiratory muscle strength was registered by maximal Inspiratory and Expiratory Pressures (PI_max and PE_max), and respiratory function by Peak Expiratory Flow (PEF). Isometric Handgrip Strength and Short Physical Performance Battery were used to evaluate peripheral skeletal muscle strength and physical performance. Univariate analysis of covariance was used with age, level of physical activity, and body mass index as covariates.

RESULTS

PI_max, PE_max, and PEF were higher in C compared to D- and D+. Exploring more in detail, PI_max, PE_max, and PEF were significantly lower in D+ compared to C. PE_max and PEF were also significantly lower in D- versus C. Measures of peripheral muscle strength and physical performance showed less associations with cdNP and T2DM.

CONCLUSIONS

The presence of cdNP affects respiratory muscle strength in T2DM patients compared to healthy controls. Both cdNP and diabetes in themselves showed a distinctive impact on respiratory muscle strength and function; however, an accumulating effect could not be ascertained in this study. As commonly used measures of peripheral muscle strength and physical performance seemed to be less affected at the given time, the integration of PI_max, PE_max, and PEF measurements in the assessment of respiratory muscle weakness could be of added value in the (early) screening for neuropathy in patients with T2DM.