Heated Tobacco Products Impair Cell Viability, Osteoblastic Differentiation, and Bone Fracture-Healing

SLR - January 2022 - Andrew J. Bloom

Reference: Nishino K,Tamai, K,Orita, K, Hashimoto Y, Nakamura H. Heated Tobacco Products Impair Cell Viability, Osteoblastic Differentiation, and Bone Fracture-Healing. J Bone Joint Surg Am. 2021 Nov 3;103(21):2024-2031.

Level of Evidence: III

Scientific Literature Review

Reviewed By: Andrew J. Bloom, DPM
Residency Program: University Hospital – Newark, NJ

Podiatric Relevance: The impact of cigarette smoking on bone healing has been well documented in that cigarette smoking negatively impact bone union. However, the effects of heated tobacco products on bone healing has not been investigated or reported until now. Heated tobacco products have been marketed as a healthy alternative to traditional tobacco products as they are operated at lower temperatures than cigarettes, therefore releasing less toxic chemicals. The aim of this study was to investigate the effects of heated tobacco products on bone union.

Methods: A level III study was performed in which cigarette smoke extracts (CSEs) were created and standardized using combustible cigarettes (cCSE) and heated tobacco products (hCSE). Preosteoblast cells were then incubated with normal medium or one of the two extracts. Cell viability and alkaline phosphatase activity after differentiation was assessed. In addition, to evaluate the direct effect on bone healing, both cCSE and hCSE extract was injected intraperitoneally into rats after a femoral midshaft fracture was created. Evaluation of bone union and a biomechanical analysis was performed four weeks later.

Results: Cell viability was reduced in both cCSE and hCSE. ALP activity was reduced significantly in cCSE and hCSE but more in cCSE. cCSE and hCSE treated rats with femoral midshaft osteotomies showed significantly decreased bone mineral content four weeks after surgery compared to the control and had significantly lower bone volumes. The rats treated with cCSE and hCSE also had significantly decreased femoral maximum load and elastic modulus when compared to the control.

Conclusions: Heated tobacco products impair bone fracture healing, cell viability and osteoblastic differentiation at a similar degree as regular cigarettes and therefore, patients should be advised to stop using heated tobacco products prior to any surgery or injury involving bone. Even though heated tobacco products have been marketed as being healthier than combustible cigarettes, this article refutes that fact when it comes to bone healing.