Box plots and results of the Tukey HSD post hoc test for total cellular NAD levels in PBMC as a function of diagnostic category. Total NAD levels were measured in 54 (24.8%) subjects (25 controls, 10 HTG and 19 NTG). Total NAD levels followed the same pattern as basal OCR, with NTG patients having the lowest NAD levels (mean (s.d.): 0.4 (±0.2) pg NAD per mg of protein), followed by HTG (mean (s.d.): 0.6 (±0.3) pg NAD per mg of protein) and controls (mean (s.d.): 0.9 (±0.3) pg NAD per mg of protein). The box plots display the distribution of total NAD values within each diagnostic category. Each box plot represents the IQR of the data, with the horizontal line inside the box indicating the median value. The lower and upper bounds of the box represent the first and third quartiles, respectively. The ‘whiskers’ extend to the minimum and maximum values within 1.5 times the IQR from the lower and upper quartiles, respectively. One-way ANOVA with Tukey’s HSD test to control family type I errors for post hoc pairwise comparisons. No adjustment for multiple comparisons was made for all other tests. Specifically, NTG versus control comparison yielded a P value of <0.0001, HTG versus control comparison yielded a P value of 0.009 and HTG versus NTG comparison yielded a P value of 0.1. Significant change with * P < 0.05, ** P < 0.01 and **** P < 0.0001.
