Surging share prices of Gautam Adani’s companies have helped make him the world’s second-richest person. The bond market isn’t quite as enthusiastic.Stocks of firms in his Indian business empire--spanning ports to gas distribution and coal mining--have jumped in part on soaring energy prices. Adani Ports & Special Economic Zone Ltd. has climbed 29% in 2022 and hit a record this week, while shares in some of his other companies have surged more than 1,000% in the past two years. But in the debt market, Adani Ports’ dollar bonds have dropped more than Indian peers on concern about the group’s debt, and its notes due in August 2027 fell to an all-time low this week, Bloomberg-compiled prices show. Bonds of group companies including Adani Green Energy Ltd. and Adani Transmission Step-One Ltd. also mostly underperformed the broader Indian market.The diverging moves suggest that high debt poses risks to Adani’s success story that saw his net worth shoot up to only trail Elon Musk’s, the Bloomberg Billionaires Index shows.The conglomerate’s rapid expansion into areas such as renewable energy and media has left it with leverage that Fitch Group unit CreditSights described as elevated and “a matter of concern.”“Equity investors are bidding up the shares, giving a premium for the steep growth targets in place,” said Hemindra Hazari, an independent research analyst based in Mumbai. “Debt holders are getting worried about the high leverage.”Adani Group declined to comment when asked about its dollar bonds underperforming Indian and regional peers. The conglomerate in the past has allayed concerns about the high debt levels, saying its credit metrics have improved in the past few years and it has received equity infusion from global investors.Adani Ports’ seven dollar-denominated notes have lost about 14% on average so far this year, while Adani Transmission Step-One’s notes due in 2036 and Adani Electricity Mumbai’s 2030 securities have lost more than 17% each. That exceeds a 10% decline for Indian dollar debt overall and a 13% drop in US currency notes in Asia excluding Japan, as rising borrowing costs in the US drag down the region’s greenback debt.Not all Adani bonds have underperformed the broader market, though, even as they’ve lost money. For instance, Adani Green Energy’s 2024 notes lost 9%, while Adani Ports’ securities due in the same year dropped 4.4%.The recent run of investments by Adani includes a plan to inject 200 billion rupees ($2.5 billion) into a cement firm that he acquired to bolster his infrastructure empire, and a $70 billion bet on green energy.Adani’s investment plan provides a “visible path for debt to increase” but a “less transparent path for EBITDA to grow,” particularly further in the future, CreditSights analysts wrote in a note this month.The Adani Group has disputed CreditSights’ assessments, saying it’s improved its debt metrics over the past decade, with the leverage ratios of its portfolio companies now “healthy” and in line with their respective industries. Adani Ports’ total debt stood at 456.4 billion rupees at the end of March, according to a statement from the group. That would be the highest in at least 10 years, data compiled by Bloomberg show. Future potential big-ticket acquisitions by the company could damage its credit profile if they’re largely debt-funded, and its leverage ratio of pro-forma net debt to EBITDA could worsen past the current 4 times, CreditSights analysts wrote in the report.For share investors, Adani companies’ growth prospects are key. Citigroup Inc. analysts pointed to Adani Ports’ increasing dominance in India’s port sector and strong operating performance, in a report this month.Adani Ports’ leading market position and strong financial management could buttress its balance sheet against short-term volume setbacks, and it may be able to maintain capital spending, investment and a 20-25% payout target via dividends and buybacks, Bloomberg Intelligence analysts Denise Wong and Sharon Chen wrote in a report last week. Bullishness toward Adani Ports has resulted in its stock trading at 25 times its one-year forward profit, making it among the most richly valued port stocks in Asia, according to Bloomberg-compiled data.