## 2 Material and Methods
### Study Procedures  
Demographic and clinical data were systematically collected for all participants. Anthropometric measurements, including height, weight, body mass index (BMI), and waist and hip circumference (WC and HC), were meticulously recorded. BMI was calculated using the formula: body weight in kilograms divided by the square of height in meters [12]. The categorization followed the guidelines established by the World Health Organization (WHO). Additionally, the waist-to-hip circumference ratio (WHR) was assessed, with a WHR value exceeding 0.85 considered indicative of risk in women [12; 13]. Non-invasive measurements of clinic systolic/diastolic brachial and central (aortic) BP levels, and heart rate were conducted using a validated cuff-based oscillometric device (Mobil-O-Graph PWA Monitor, I.E.M. GmbH, Stolberg, Germany), as previously described [14]. Briefly, three consecutive BP measurements were taken at 1-min intervals, with the average of the three considered the reference value for clinical BP. The central \begin{table}
\begin{tabular}{c c c c c} \hline  & **MWGG (_n = 12_)** & **Max-Min** & **MWMG (_n = 8_)** & **Max-Min** \\ \hline Age (years) & & & & \\ \hline (Mean \(\pm\) SD, range) & 56.08 \(\pm\) 4.99 & 49–65 & 54.85 \(\pm\) 5.75 & 46–60 \\ \hline Menarche years (years) & & & & \\ \hline (Mean \(\pm\) SD, range) & 11.58 \(\pm\) 0.99 & 10–13 & 11.86 \(\pm\) 1.06 & 10–13 \\ \hline Menopause years (years) & & & & \\ \hline (Mean \(\pm\) SD, range) & 51.33 \(\pm\) 3.22 & 45–56 & 50.00 \(\pm\) 3.06 & 44–54 \\ \hline Years since menopause (years) & & & & \\ \hline (Mean \(\pm\) SD, range) & 4.75 \(\pm\) 2.89 & 2–9 & 4.86 \(\pm\) 2.67 & 2–9 \\ \hline Menopausal Weight Gain (Kg) & & & & \\ \hline (Mean \(\pm\) SD, range) & 10.25 \(\pm\) 2.92 & 2–13 & 2 \(\pm\) 1 & 0–3 \\ \hline \multicolumn{5}{c}{**MWGG (_n = 12_)**} & **MWMG (_n = 8_)** \\ \hline Smoker (\%) & 8.33 & & 14.28 & \\ \hline Diabetes (\%) & 8.33 & & 14.28 & \\ \hline Dislipidemia (\%) & 50.00 & & 28.57 & \\ \hline Anti-hypertensive Drugs (\%) & & & & \\ \hline
0 & 8.33 & & 14.28 & \\ \hline
1 & 50.00 & & 71.44 & \\ \hline
2 & 25.00 & & 14.28 & \\ \hline
3 or more & 16.67 & & 0 & \\ \hline \end{tabular}
\end{table} 
Table 1: Characteristics of study participants. Patients were categorized as MWGG for the menopausal weight gain group or MWMG for the menopausal weight maintenance group. aortic BP was measured following a 30-s interval after the last clinic BP measurement, using appropriately sized cuffs or larger or smaller cuffs for obese or thin subjects, respectively, according to European guidelines [15]. All participants underwent a resting 12-lead electrocardiogram (ECG) while in the supine position, utilizing a Mortara Eli 350 ECG device (Milwaukee, WI, USA). The ECGs were recorded with a paper speed of 25 mm/s and a calibration of 1 mV/cm. Each ECG was then scanned at 600 dpi, allowing for both conventional and novel ECG parameters to be analyzed on a high-resolution computer monitor. We assessed heart rate (HR) and conventional ECG parameters, including PR interval, QRS duration, QT and QTc intervals, and left ventricular hypertrophy (LVH) indexes, as recommended by current European guidelines [15] and as applied in previous studies [14]. After a 8-h overnight fast, all subjects underwent whole-body and segmental fat mass (measured in kilograms) assessment, employing Dual-Energy X-ray Absorptiometry (DXA) scans, a Primus X-ray densitometer, and software version 1.2.2 (Osteosys Co., Ltd., Guro-gu, Seoul, Korea). All individuals were instructed to remove their clothes (except underwater), shoes, and any metal object before being measured. The total fat mass percentage (%FM) was determined by dividing the total body fat mass (Total FM) by the combined mass of all tissues, including the total body bone (TBBone).