Systemic sclerosis (SSc) is an autoimmune disorder with high mortality due to excessive accumulation of collagen in the skin and internal organs. An accurate and early diagnosis is crucial to ensure effective treatment. Currently, the modified Rodnan skin score (mRSS) is the gold standard for evaluating dermal thickening during SSc onset and progression. However, obtaining the mRSS can be time consuming, and the score has noticeable inter- and intraobserver variabilities. Optical coherence elastography (OCE) is an emerging technique for measuring soft tissue biomechanical properties completely noninvasively. In this work, we demonstrate the first use of OCE combined with analysis of the OCT signal slope (OCTSS) for sclerosis detection in the dorsal forearm of 12 patients. A comparison to clinical diagnoses including dermal thickness assessed by histology, mRSS, and site specific mRSS (SMRSS). Results of both optical assessments demonstrated high correlation (OCE: 0.78 and OCTSS: 0.65) with SMRSS as performed by an experienced physician. Importantly, the correlation of both proposed parameters with the dermal thickness (OCTSS: r=0.78 and OCE: r=0.74) outperformed the SMRSS assessment (r=0.57), demonstrating the effectiveness of using OCT/OCE for monitoring the disease severity of SSc.