Relationship between anthropometric and biochemical changes of metabolic syndrome with retinal nerve fiber layer and macular thickness.

ABSTRACT:

Objective

To evaluate the retinal nerve fiber layer (RNFL) and macular thicknesses and identify systemic risk factors for thinning of these layers in patients with metabolic syndrome (MetS).

Methodology

A cross-sectional observational study was performed on patients diagnosed with MetS and compared to normal controls. All patients underwent ophthalmic and anthropometric examination, serological and biochemical blood investigations; and ocular imaging using spectral-domain optical coherence tomography. Patients with ocular pathology were excluded. Unpaired t-test was used to compare mean thickness between the two groups. One-way ANOVA with Bonferroni correction for multiple comparisons was used to compare mean thickness between different tertiles of MetS parameters, and a generalized estimating equation was used to correct for inter-eye correlation and to assess association between mean thickness and covariates.

Results

Two hundred and forty-eight eyes from 124 participants (1:1 ratio of MetS patients to controls) were included. Age ranged between 30 to 50 years old, and mean age was 40 ± 6.6 years. RNFL thickness was lower globally (93.6 ± 9.9 ?m vs 99.0 ± 9.3, p<0.001) and in the inferior (124.5 ± 17.5 ?m vs 131.0 ± 16.4 ?m, p = 0.002), superior (117.2 ± 16.0 ?m vs 126.3 ± 14.4 ?m, p<0.001) and temporal (65.5 ± 10.2 ?m vs 69.5 ± 9.8, p = 0.002) sectors in MetS patients compared to controls. Only the central (237.0 ± 14.0 ?m vs 243.6 ± 18.0 ?m, p = 0.002) and inferior parafoveal (307.8 ± 20.9 vs 314.6 ± 14.6, p = 0.004) area of the macula was significantly thinner. The inferior RNFL sector had the most difference (mean difference = 9.1 ?m). The Generalized Estimating Equation found that, after adjusting for age, diastolic blood pressure, BMI, HDL and obesity; the number of MetS components and elevated triglyceride levels were independent risk factors for reduced thickness in global RNFL (? = -4.4, 95% CI = -7.29 to -1.5, p = 0.003) and inferior parafovea (? = -6.85, 95% CI = -11.58 to -2.13, p = 0.004) thickness respectively.

Conclusion

RNFL thinning was seen more than macula thinning in MetS patients, suggesting RNFL susceptibility to neurodegeneration than the macula. A higher number of metabolic components and elevated triglyceride levels were independent risk factors for retinal thinning in this group of patients.

SUBMITTER: New SH 

PROVIDER: S-EPMC7906412 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature