SAO PAULO, May 14 (Reuters) - Brazilian digital lender

Nubank's adjusted net profit more than doubled in the

fist quarter when compared to the year-earlier period,

surpassing analysts estimates, as growth in its credit loan

portfolio boosted revenues.

Nubank's adjusted net profit surged 143% to $442.7 million

from the year earlier, while analysts polled by LSEG expected a

$404.8 million adjusted profit. Profit was up despite rising

loans overdue rates raised some concerns.

Its return on equity (ROE) - a measure of financial

performance - came in at 23%, stable from the fourth quarter,

but up from 11% a year ago.

Earlier this month, Nubank said it has exceeded 100 million

customers in Latin America, making it the first digital banking

platform outside Asia to do so.

More than 90 million of these customers are in Brazil, while

the digital lender has also been growing in Mexico and, more

recently, in Colombia.

The lender's revenue rose 69% in the quarter to $2.74

billion, above analysts estimates of $2.49 billion. Net interest

income almost doubled year-on-year, with Nubank attributing the

performance to the grow of personal loan and credit cards

portfolio.

However, the lender's loans overdue by 15 to 90 days in

Brazil increased 0.6 percentage points in 12 months to 5%. Loans

overdue by more than 90 days were at 6.3% from 5.5%. They both

also rose from the fourth quarter.

Nubank said its short-term delinquency rates were impacted

by seasonal effects, while longer rates followed "the expected

stacking behavior of the early delinquency buckets in previous

periods".

"Nubank presented another quarter of earnings growth,

combined with positive business expansion trends", Santander

analyst Henrique Navarro wrote in a report, while raising

concerns on assets quality.

"Asset quality was a lowlight, in our view, and this might

raise some concerns regarding credit quality deterioration in

upcoming quarters", Navarro said.

(Reporting by Andre Romani and Patricia Vilas Boas in Sao Paulo

Editing by Valentine Hilaire, Matthew Lewis and Lincoln Feast.)